About the ionization process the Edgard Var se composition Ionisation Var se File Ionization energies.svg right thumb 400px Ionization energies of neutral elements. Ionization is the process of converting ... seem as a case of ionization, in reality the ions already exist within the crystal lattice. When ... occurs whatsoever. Actually, the chemical synthesis of salt involves ionization. This is a chemical reaction. The process of ionization works slightly differently depending on whether an ion with a positive .... The amount of energy required is called the ionization energy . A negatively charged ion is produced ... barrier, releasing any excess energy. In general, ionization can be broken down into two types sequential ionization and non sequential ionization . In classical physics, only sequential ionization can take place refer to the Classical ionization Classical ionization section for more information. Non sequential ionization violates several laws of classical physics refer to the Quantum ionization Quantum ionization section. Classical ionization Applying only classical physics and the Bohr model of the atom makes both atomic and molecular ionization entirely Scientific determinism deterministic ... to positive ionization According to these two principles, the energy required to release an electron ... the lowest available state. Applying to negative ionization Due to the shape of the potential ... barrier. Sequential ionization Sequential ionization is a description of how the ionization of an atom ..., always moving from one number to an adjacent, or sequential , number. Quantum ionization In quantum mechanics , ionization can still happen classically, whereby the electron has enough energy to make it over the potential barrier, but there is the additional possibility of tunnel ionization . Tunnel ionization Tunnel ionization is ionization due to quantum tunneling . In classical ionization ... through and, thus, a greater chance to do so. Non sequential ionization When the fact that the electric ... more details
Distinguish chemical ionization Chemi ionization is the formation of an ion through the reaction of a gas phase atom or molecule with an atom or molecule in an excited state . ref GoldBookRef title chemi ionization file C01044 C01044 ref ref name Klucharev1993 citation last Klucharev first A. N. year 1993 title Chemi ionization processes journal Physics Uspekhi volume 36 pages 486 doi 10.1070 PU1993v036n06ABEH002162 bibcode 1993PhyU...36..486K issue 6 ref Reactions Chemi ionization can be represented by math G M to M bullet e G math where G is the excited state species indicated by the superscripted asterisk , and M is the species that is ionized by the loss of an electron to form the Radical chemistry radical cation indicated by the superscripted plus dot . See also Penning ionization Associative ionization Charge exchange ionization References Reflist atomic physics stub Category Ion source it Ionizzazione chimica ... more details
Associative ionization is a gas phase reaction in which two atom s or molecule s interact to form a single product ion . ref GoldBookRef title associative ionization file A00475 ref One or both of the interacting species may have excess internal energy . For example math A B to AB bullet e math where species A with excess internal energy indicated by the asterisk interacts with B to form the ion AB sup sup . See also Chemi ionization Penning ionization References Reflist References Reflist refbegin cite journal author Jones DM, Dahler JS title Theory of associative ionization year 1988 month April pmid 9900022 journal Physical Review A volume 37 issue 8 pages 2916 2933 doi 10.1103 PhysRevA.37.2916 Cite journal last Cohen first James S. year 1976 title Multistate curve crossing model for scattering Associative ionization and excitation transfer in helium journal Physical Review A volume 13 pages 99 doi 10.1103 PhysRevA.13.99 refend Category Ion source atomic physics stub ... more details
Adiabatic ionization is a form of ion ization in which an electron is removed from or added to an atom or molecule in its lowest energy state to form an ion in its lowest energy state. ref GoldBookRef title adiabatic ionization file A00143 ref See also Adiabatic process References Reflist atomic physics stub Category Mass spectrometry ... more details
In accelerator physics , ionization cooling is a process by which the beam emittance emittance of a charged particle beam can be reduced . ref G.I. Budker, in Proceedings of 15th International Conference on High Energy Physics, Kiev, 1970 A.N. Skrinsky, Intersecting storage rings at Novosibirsk, in Proceedings of Morges Seminar, 1971 Report CERN D.PH II YGC mng ref In ionization cooling, particles are passed through some material. The momentum of the particles is reduced as they ionize atomic electrons in the material. Thus the normalised beam emittance is reduced. By re accelerating the beam, for example in an RF cavity, the longitudinal momentum may be restored without replacing transverse momentum. Thus overall the angular spread and hence the geometric emittance in the beam will be reduced. Ionization cooling can be spoiled by stochastic physical processes. Multiple Coulomb scattering in muons as well as nuclear scattering in protons and ions can reduce the cooling or even lead to net heating transverse to the direction of beam motion. In addition, energy straggling can cause heating parallel to the direction of beam motion. Muon cooling The primary use of ionization cooling is envisaged to be for cooling of muon beams. This is because ionization cooling is the only technique that works on the timescale of the muon lifetime. Ionization cooling channels have been designed for use in a Neutrino Factory and a Muon Collider . Muon ionization cooling is expected to be demonstrated for the first time by the Proof of Principle International Muon Ionization Cooling Experiment . Other PoP muon ionization cooling experiments have been devised. Other particles Ionization cooling has also been proposed for use in low energy ion beams and proton beams. Longitudinal cooling The technique can be adapted to provide longitudinal as well as transverse cooling by using a dipole magnet ... Ionization Cooling Category Accelerator physics Category Particle physics ... more details
Technical date September 2010 Thermal ionization , also known as surface ionization , refers to the process whereby a chemically purified material is placed onto a Electrical filament filament which is then heated to high temperatures to cause some of the material to be ion ized as it is thermally desorbed boiled off the hot filament. Filaments are generally flat pieces of metal around 1 2mm wide, 0.1mm thick, bent into an upside down U shape and attached to two contacts that supply a current. Saha Langmuir equation The likelihood of ionization is a function of the filament temperature, the work function of the filament substrate and the ionization energy of the chemical element element . This is summarised in the Megh Nad Saha Saha Irving Langmuir Langmuir equation ref name 1.1655755 Cite journal title The Saha Langmuir Equation and its Application journal Journal of Applied Physics date January 1968 first M. J. last Dresser coauthors volume 39 issue 1 pages 338 339 doi 10.1063 1.1655755 url http scitation.aip.org getpdf servlet GetPDFServlet?filetype pdf&id JAPIAU000039000001000338000001&idtype cvips&prog normal format PDF accessdate 2007 10 11 bibcode 1968JAP....39..338D ref math frac n n 0 frac g g 0 exp Bigg frac e phi IP kT Bigg math math frac n n 0 math ratio of ion number ... ionization potential k Boltzmann s constant T surface temperature Thermal ionization mass spectrometry One application of thermal ionization is thermal ionization mass spectrometry TIMS . This method ... for species with a low ionization energy, such as Strontium Sr , and Lead Pb . The disadvantages of this method stem from the maximum temperature achieved in thermal ionization. The hot filament ... ions of species with a high ionization energy, such as Osmium Os , and Tungsten Hf W . Although the TIMS method can create molecular ions instead in this case, species with high ionization energy ... DEFAULTSORT Thermal Ionization mass spectrometry Category Ion source et Termoionisatsioon it Ionizzazione ... more details
Electron ionization EI , formerly known as electron impact is an ionization method in which energetic electron s interact with gas phase atoms or molecules to produce ion s. ref GoldBookRef title electron ionization file E01999 ref This technique is widely used in mass spectrometry , particularly for gases and volatile organic chemistry organic molecules . Principle of operation Image Schematic diagram of an EI ion source.jpg thumb right 300 px Diagram representing an electron ionization ion source The following Phase matter gas phase reaction describes the electron ionization process ref R. Davis, M. Frearson, 1987 . Mass Spectrometry Analytical Chemistry by Open Learning , John Wiley & Sons, London. ref math M e to M bullet 2e , math where M is the analyte molecule being ionized, e sup sup is the electron and M sup sup is the resulting ion . In an EI ion source , electrons are produced ... electrons, referred to as a hard ionization source, causes large fluctuations in the electric field around the neutral molecules and induces ionization and fragmentation. ref K. Robinson et al. Undergraduate ... cation products are then directed towards the mass analyzer by a repeller electrode. The ionization ... detection and signal processing, convey structural information about the analyte. The ionization ... and the analyte molecules do not transfer enough energy to cause ionization. At around 70 ..., leading to the strongest possible ionization and fragmentation. Under these conditions, about 1 in 1000 ... to the electrons and ionization efficiency decreases. Notes Reflist References refbegin cite ... Stephen J. Schrader title Interpretation of Electron Ionization Data The Odd Book publisher Not Avail ... title Theory of ionization of atoms by electron impact publisher Colorado Associated University ... title Electron impact ionization publisher Springer Verlag location Berlin year 1985 pages isbn ...&Units SI&Mask 200 Mass Spec NIST Chemistry WebBook Mass spectrometry DEFAULTSORT Electron Ionization ... more details
Penning ionization is a form of chemi ionization , an ionization process involving reactions between neutral atoms or molecules. ref name pmid17155624 cite journal author Arango CA, Shapiro M, Brumer P title Cold atomic collisions coherent control of penning and associative ionization journal Phys. Rev. Lett. volume 97 issue 19 pages 193202 year 2006 pmid 17155624 doi 10.1103 PhysRevLett.97.193202 bibcode 2006PhRvL..97s3202A ref ref name pmid17016831 cite journal author Hiraoka K, Furuya H, Kambara S, Suzuki S, Hashimoto Y, Takamizawa A title Atmospheric pressure Penning ionization of aliphatic hydrocarbons journal Rapid Commun. Mass Spectrom. volume 20 issue 21 pages 3213 22 year 2006 pmid 17016831 doi 10.1002 rcm.2706 ref The process is named after the Dutch physicist Frans Michel Penning who first reported it in 1927. ref Penning, F. M. Die Naturwissenschaften , 1927, 15 , 818. ber Ionisation durch metastabile Atome. ref The Penning effect is put to practical use in applications such as gas discharge neon lamp s and fluorescent lamp s, where the lamp is filled with a Penning mixture to improve the electrical characteristics of the lamps. Reactions Penning ionization refers to the interaction between a gas phase excited state atom or molecule G sup sup and a target molecule M resulting in the formation of a radical molecular cation M sup . sup , an electron e sup sup , and a neutral gas molecule G ref GoldBookRef title Penning gas mixture file P04476 ref math G M to M bullet e G math Penning ionization occurs when the target molecule has an ionization potential lower than the internal energy of the excited state atom or molecule. associative ionization Associative Penning ionization can also occur math G M to MG bullet e math Surface Penning ionization refers to the interaction of the excited state gas with a surface S, resulting in the release of an electron. math ... effect. See also Chemical ionization References reflist Category Ion source it Ionizzazione di ... more details
morefootnotes date December 2008 File Electron binding energy vs Z.jpg thumb 200px The ionization energy ... gaseous atoms or ions. The property is alternately still often called the ionization potential , measured in volts. In chemistry it often refers to one mole of a substance molar ionization energy or enthalpy and reported in kJ mol. In atomic physics the ionization energy is typically measured in the unit electron volt eV . Large atoms or molecules have a low ionization energy, while small molecules tend to have higher ionization energies. The ionization energy is different for electrons of different atomic or molecular orbitals. More generally, the n th ionization energy is the energy required to strip off the n th electron after the first math n 1 math electrons have been removed. Ionization ... binding the greater the ionization energy, the more difficult it is to remove an electron. The ionization energy may be an indicator of the reactivity of an element. Elements with a low ionization ... and trends Main article Molar ionization energies of the elements Generally the n 1 th ionization energy is larger than the n th ionization energy. Always, the next ionization energy involves removing ... forces of electrostatic attraction thus, their removal requires increasingly more energy. Ionization ... molar ionization energies in joule kJ mole unit mol br 96.485 kJ mol 1 electron volt eV particle Element ... binding energy vs Z.jpg thumb 500px Large jumps in the successive molar ionization energies occur when ... molar ionization energies of magnesium stripping the two 3s electrons from a magnesium atom are much ... of Mg sup 2 sup . Image IonizationEnergyAtomicWeight.PNG thumb 300px Periodic trend for ionization ... gases. Ionization energy is also a periodic trend within the periodic table organization. Moving ... , the first ionization energy generally increases. As the atomic radius decreases, it becomes harder to remove an electron that is closer to a more positively charged nucleus. ionization enthalpy increases ... more details
Tunnel ionization is a process in which electron s in an atom or a molecule pass through the potential barrier and escape from the atom or molecule . In an intense electric field , the potential barrier ... ionization come and go to the atom molecule in every half period. In this process, some electrons ... light . When the recombination does not occur, further ionization proceeds by collision between ... The tunneling ionization rate for the hydrogen atom in an electrostatic field using the semi ... , 2nd ed., pg 276. Tunnel Ionization probability for H like atoms considering potential well was initially proposed by Keldysh Sov. Phys. JETP, 1965 . Theory extended to ionization from excited electronic ... et al. ADK, JETP, 1986 . Tunneling Ionization of atoms was first observed experimentally by Chin ... Augst et al. J. Opt. Soc. Am, 1991 etc. Theoretical and Experimental works regarding ionization related ... work of ADK is so far the most valid and highly appreciated theory. Physical Process Tunneling Ionization ... ionization. Notation math E a math is the characteristic atomic electric field the electric field at the bohr radius math omega a math is the frequency associated with the ionization energy i.e. ... constant math epsilon 0 math is the Permittivity dielectric constant DC Tunneling Ionization Tunneling ionization from the ground state of a Hydrogen atom in an electrostatic DC field was solved ... exponential dependence of the ionization rate on the applied external field. When math E E a math , the ionization rate for this system is given by math w 4 omega a frac E a left E right exp left frac ... m 2 e 5 4 pi epsilon 0 3 hbar 4 math , math omega a frac m e 4 4 pi epsilon 0 2 hbar 3 math . The ionization ... coulomb potential barrier. AC Electric Field The ionization rate of an hydrogen atom in an alternating electric field, like that of a laser, can be treated, in the appropriate limit, as the DC ionization ... Tunnel Ionization Category Ions Category Atomic physics de Tunnelionisation zh ... more details
Chemical ionization CI is an ionization technique used in mass spectrometry . ref Munson, M.S.B. Field, F.H. J. Am. Chem. Soc. 1966 , 88 , 2621 2630. http dx.doi.org 10.1021 ja00964a001 Chemical Ionization ... of electron ionization and chemical ionization mass spectrometry journal Recent Prog. Horm. Res ... Dougherty RC title Negative chemical ionization mass spectrometry applications in environmental ... doi 10.1002 bms.1200080702 ref Chemical ionization is a lower energy process than electron ionization ... reagent gas molecules will create an ionization plasma physics plasma . Positive and negative ... 4 A math Charge exchange ionization charge exchange Self chemical ionization occurs when the reagent ion is an ionized form of the analyte. ref Cite journal doi 10.1021 ac00226a011 title Chemical ionization ... issue 3 ref Variations NGI, ECNCI redirects here Negative chemical ionization NCI Chemical ionization ... ions through the reactions described above. In order to see a response by negative chemical ionization ... by electron capture ionization . Because not all analytes can do this, using NCI provides a certain degree of selectivity that is not available with other, more universal ionization techniques EI, PCI ... chromatography mass spectrometry with negative chemical ionization for exposure estimation journal ... volumes 100 l of plasma of wild birds through gas chromatography negative chemical ionization mass ... . Atmospheric pressure chemical ionization APCI Chemical ionization in an atmospheric pressure electric discharge is called atmospheric pressure chemical ionization . The analyte is a gas or liquid spray and ionization is accomplished using an atmospheric pressure corona discharge. This ionization ... www.chem.harvard.edu mass tutorials ci.html Chemical Ionization Tutorial GoldBookRef title chemical ionization in mass spectrometry file C01026 Mass spectrometry States of matter DEFAULTSORT Chemical Ionization Category Ion source Category Mass spectrometry Category Scientific techniques de Chemische ... more details
Unreferenced stub auto yes date December 2009 File ImpactIonisation1.svg thumb 350px ImpactIonisation1 An example of an incoming electron impact ionizing to produce a new electron hole pair File Impact ionization schematic.svg thumb 350px An example of impact ionization in a semiconductor. Impact ionization is the process in a material by which one energetic charge carrier can lose energy by the creation of other charge carriers. For example, in semiconductor s, an electron or Electron hole hole with enough kinetic energy can knock a bound electron out of its bound state in the valence band and promote it to a state in the conduction band , creating an electron hole pair . If this occurs in a region of high electrical field then it can result in avalanche breakdown . This process is exploited in avalanche diode s, by which a small optical signal is amplifier amplified before entering an external electronic circuit. In an avalanche photodiode the original charge carrier is created by the absorption of a photon . In some sense, impact ionization is the reverse process to Auger electron Auger recombination . Avalanche photodiodes APD s are used in Optical receivers before the signal is given to the receiver circuitry the photon is multiplied with the photocurrent and this increases the sensitivity of the receiver since photocurrent is multiplied before encountering of the thermal noise associated with the receiver circuit See also Avalanche breakdown Avalanche diode Avalanche photodiode External links http impact ionisation.group.shef.ac.uk tools Animation showing impact ionization in a semiconductor DEFAULTSORT Impact Ionization Category Semiconductors Category Article Feedback 5 Nuclear stub de Sto ionisation lt Sm gin jonizacija ja pl Jonizacja zderzeniowa ru uk ... more details
Spark ionization also known as spark source ionization wikt deprecated deprecated is a method used to produce gas phase ion s from a solid sample. The prepared solid sample is vaporized and partially ionized by an intermittent discharge or spark. ref http www.iupac.org goldbook S05780.pdf IUPAC gold book definition ref This technique is primarily used in the field of mass spectrometry . When incorporated with a mass spectrometer the complete instrument is referred to as a spark ionization mass spectrometer or as a spark source mass spectrometer SSMS . ref cite journal author H. E. Beske, A. Hurrle and K. P. Jochum title Part I. Principles of spark source mass spectrometry SSMS year 1981 journal Fresenius Journal of Analytical Chemistry volume 309 issue 4 pages 258 261 doi 10.1007 BF00488596 ref Sample preparation Typically samples are physically incorporated into two conductive electrode s usually either carbon or silver between which a high voltage electric spark is produced, ionizing the material at the tips of the electrodes. If metals are being analyzed the sample may serve as an electrode. Technical information Mass analyzers are typically Sector instrument Mattauch Herzog geometry, and use either photosensitive plates for ion detection or linear channeltron detector arrays. References refbegin reflist refend Mass spectrometry DEFAULTSORT Spark Ionization Category Ion source it Ionizzazione a scintilla ... more details
Ambient ionization is a form of ion ization in which ions are formed outside the mass spectrometer without sample preparation or separation. ref name Cooks2006 Cite journal last1 Cooks first1 R. Graham last2 Ouyang first2 Zheng last3 Takats first3 Zoltan last4 Wiseman first4 Justin M. year 2006 title Ambient Mass Spectrometry journal Science volume 311 issue 5767 pages 1566 70 doi 10.1126 science.1119426 pmid 16543450 postscript None bibcode 2006Sci...311.1566C ref Direct analysis in real time main DART ion source Direct analysis in real time DART is an atmospheric pressure ion source that operates by exposing the sample to a gas stream typically helium or nitrogen that contains long lived electronically or excited neutral atoms , vibronically excited molecules or Metastability in molecules ... of Materials in Open Air under Ambient Conditions ref Desorption electrospray ionization main Desorption electrospray ionization Desorption electrospray ionization DESI uses an electrospray ... RG title Ambient mass spectrometry using desorption electrospray ionization DESI instrumentation, mechanisms ... 17803282 ref Laser assisted Electrospray assisted laser desorption ionization ELDI relies on a laser ... desorption ionization mass spectrometry for direct ambient analysis of solids journal Rapid Commun ... assisted laser desorption electrospray ionization MALDESI , a nitrogen laser is used to desorb ... laser desorption electrospray ionization MALDESI Fourier transform ion cyclotron resonance mass ... ablation electrospray ionization LAESI uses an infrared laser for ablation of the sample material. ref name pmid17900146 cite journal author Nemes P, Vertes A title Laser Ablation Electrospray Ionization ... ionization has been used to describe transmission mode laser ablation of matrix analyte mixtures ... MCP200 title Laserspray Ionization, a New Atmospheric Pressure MALDI Method for Producing ... also Atmospheric pressure chemical ionization References Reflist Mass spectrometry Category Mass spectrometry ... more details
Image Plasma lamp 2.jpg thumb 300px right A plasma globe plasma lamp , illustrating a low degree of ionization i.e. a partially ionized gas The degree of ionization also known as ionization yield in the literature refers to the proportion of neutral particles, such as those in a gas or aqueous solution, that are ionized into charged particles. A low degree of ionization is sometimes called partially ionized , and a very high degree of ionization as fully ionized . Ionization refers to the process whereby an atom or molecule loses an electron , resulting in two oppositely charged particles, 1 a negatively charged electron and 2 a positively charged ion . Chemistry usage The degree of ionization , or , is a way of representing the strength of an acid, often represented by the Greek letter alpha. It is defined as the ratio between the number of ionized molecules and the number of molecules dissolved in water. It can be represented as a decimal number or as a percentage. One can classify strong acids as having ionization degrees above 50 , weak acids with below 50 , and the remaining as moderate acids, at a specified molar concentration. Physics usage In gases and Plasma physics plasma , the degree of ionization refers to the proportion of neutral particles that are ionized into charged particles. For example, when electricity passes through a novelty plasma ball , perhaps 1 of the gases are ionized sometimes referred to as partially ionized . Our Sun and all stars contain largely hydrogen and helium gases, that are fully ionized into electrons, protons H sup sup and helium ions He sup sup . A gas may begin to behave like plasma when the degree of ionization is as little as 0.01 . ref Brian Chapman, Glow discharge plasmas. p49 ref ref Shibamoto, Takayuki. Introduction to Food Toxicology, 2nd Edition. Academic Press, 2009. p17. ref History Ionized matter was first identified in a discharge tube or Crookes tube , and so described by Sir William Crookes in 1879 he called ... more details
The Ionization chamber is the simplest of all gas filled radiation detectors, and is used for the detection or measurement of ionizing radiation . Conventionally, the term ionization chamber is used exclusively to describe those detectors which collect ion pairs from gases. ref cite book first Glenn F last Knoll title Radiation detection and measurement edition 3rd year 1999 location New York publisher Wiley isbn 0 471 07338 5 ref Construction and operation File Ionization chamber.svg thumb right Ion chamber, showing drift of ions. Incident radiation is the dotted line. An ionization chamber is an instrument constructed to measure charge from the number of ion s within a medium which we will consider to be gaseous, but can also be solid or liquid . It usually consists of a gas filled enclosure between two conducting electrodes the anode and cathode . The electrodes may be in the form of parallel plates Parallel Plate Ionization Chambers PPIC , or coaxial cylinders to form a convenient portable detector in some cases one of the electrodes may be the wall of the vessel itself. When gas between the electrodes is ionized by any means, such as by alpha particle s, beta particle s, X ray s, or other radioactive emission, the ions and dissociated electrons move to the electrodes of the opposite Chemical polarity polarity , thus creating an ionization current which may be measured by a galvanometer or electrometer . Each ion essentially deposits or removes a small electric charge to or from ... Ionization chambers are widely used in the nuclear industry as they provide an output that is proportional ... The ionization chamber has found wide and beneficial use in smoke detectors. In a smoke detector ... amount of energy, and when they collide with gas in the ionization chamber mostly nitrogen ... physics and radiotherapy , ionization chambers are used to ensure that the dose delivered from a therapy ... . Ionization chambers are connected to electrometers, and they typically report a collected ... more details
Image NanoESIFT.jpg right thumb Electrospray nanoSpray ionization source Electrospray ionization ESI is a technique used in mass spectrometry to produce ions. It is especially useful in producing ions .... The development of electrospray ionization for the analysis of biological macromolecules ref cite journal author Fenn, J. B. Mann, M. Meng, C. K. Wong, S. F. Whitehouse, C. M. title Electrospray ionization ... is called electrospray ionization mass spectrometry ESI MS or, less commonly, electrospray mass spectrometry ES MS . History File Fenn ESI Instrument.jpg thumb Fenn s first electrospray ionization source ... Geoffrey Ingram Taylor Ionization mechanism The liquid containing the analyte s of interest is Electrospray ... extensive solvent evaporation, the typical solvents for electrospray ionization are prepared by mixing ... in some other ionization sources. The analytes are sometimes involved in Electrospray Closing the electrical ... droplets, which ensure improved ionization efficiency. In 1994, two research groups coined the name ... pages 435 442 year 1998 title Equilibrium unfolding of proteins monitored by electrospray ionization ... Complexation Changes in Proteins during Electrospray Ionization ref ref Cite author Sobott Robinson ... LC MS main liquid chromatography mass spectrometry Electrospray ionization is the ion source ... gas phase interactions Electrospray ionization is also ideal in studying noncovalent gas phase interactions ... Taylor cone Desorption electrospray ionization Sonic spray ionization References Reflist Bibliography refbegin cite book author Cole, Richard title Electrospray ionization mass spectrometry ... applications of electrospray ionization mass spectrometry publisher American Chemical Society ... education tutorials tools ionization esi.html Electrospray Ionization Primer National High Magnetic Field Laboratory MeshName Electrospray Ionization Mass Spectrometry http www.newobjective.com electrospray New Objective What is Electrospray? Mass spectrometry DEFAULTSORT Electrospray Ionization ... more details
Charge exchange ionization also known as charge transfer ionization is a gas phase reaction between an ion and an atom or molecule in which the charge of the ion is transferred to the neutral species. ref GoldBookRef title charge exchange ionization file C00989 ref For example math A B to A B math . See also Associative ionization Chemi ionization Penning ionization References Reflist refbegin refend atomic physics stub Category Ion source it Ionizzazione per scambio di carica simmetrico ... more details
Infobox chemical analysis name Desorption Electrospray Ionization DESI image caption acronym DESI classification Mass spectrometry analytes Organic molecule s br Biomolecule s related Electrospray ionization br Atmospheric pressure chemical ionization hyphenated Desorption electrospray ionization DESI is an ambient ionization technique that can be used in mass spectrometry for chemical analysis . It is an atmospheric ... Electrospray Ionization journal Science volume 306 pages 471 473 year 2004 doi 10.1126 science.1104404 pmid 15486296 issue 5695 ref DESI is a similar ionization technique to Direct Analysis ... is a combination of electrospray ESI and desorption DI ionization methods. Ionization takes place by directing ... desorption electrospray ionization DESI instrumentation, mechanisms and applications in forensics ... a voltage on the sample holder. After ionization, the ions travel through air into the atmospheric ... for ambient ionization of a trace sample at atmospheric pressure, with little sample preparation. Ionization mechanism In DESI there are two kinds of ionization mechanism, one that applies to low ... is a combination of methanol and water. For the low molecular weight molecules, ionization ... S s , qquad 2 math math A g S g to A g S g , qquad 3 math The ionization mechanism of low molecular weight molecules in DESI is similar to DART ion source DART s ionization mechanism, in that there is a charge transfer that occurs in the gas phase. Ionization efficiency Image DESI side view.jpg thumb ... parameters The ionization efficiency of DESI is complex and depends on several parameters such as, surface ..., , d sub 1 sub and d sub 2 sub see figure on the right . Furthermore, and d sub 1 sub affect the ionization ... has a different ionization mechanism described in detail in the Principle of operation section. The sprayer ... External links http aston.chem.purdue.edu research ionization desorption electrospray ionization desi ... for Desorption Electrospray Ionization US patent application 20050230635 Method and System ... more details
Infobox chemical analysis name Probe Electrospray Ionization PESI image PESI.png caption Conceptual diagram of the PESI ion source acronym PESI classification Mass spectrometry analytes Organic molecule s br Biomolecule s related Electrospray ionization hyphenated Probe electrospray ionization PESI is a modified version of conventional electrospray ionization ESI , where the capillary for sample solution transferring is replaced by a solid needle with a sharp tip. PESI was first introduced by Kenzo Hiraoka et al. in 2007 ref cite journal author Hiraoka K. Nishidate K. Mori K. Asakawa D. Suzuki S. title Development of probe electrospray using a solid needle journal Rapid Communications in Mass Spectrometry year 2007 volume 21 pages 3139 3144 doi 10.1002 rcm.3201 pmid 17708527 issue 18 ref . Compared with conventional electrospray ionization , high salt tolerance and direct sampling and low sample consumption can be found with PESI. Of course, PESI is not a continuous process at all. Normally, the needle for sampling and spraying can be driven up and down under a frequency of 3 5 Hz. References Reflist Mass spectrometry DEFAULTSORT Probe Electrospray Ionization Category Ion source Category Mass spectrometry ... more details
Atmospheric pressure laser ionization is an atmospheric pressure ionization method for Mass spectrometry ... enhanced multiphoton ionization REMPI process. It is a selective and sensitive ionization method for aromatic and polyaromatic compounds. Ionization principle File APLI mechanism.png thumb APLI Ionization ... high photon fluxes, the ionization potential is reached One electron is removed from the molecule and a radical cation is formed. For efficient ionization by the absorption of two photons a high density ... must be above the ionization potential of the atom or molecule. In the simplest case, a single photon has sufficient energy to overcome the ionization potential. This process is therefore called single photon ionization, it is the basic principle of Atmospheric pressure photo ionization .... If the combined energy of the absorbed photons is higher than the ionization potential, this multiphoton absorption process can also lead to ionization of the atom or molecule. This process is called multi photon ionization MPI . The laser light sources used in APLI have power densities which allow multiphoton ionization via stable electronic states of the molecule or atom. The required power ... 5 text eV M cdot e math This process is called REMPI resonance enhanced multi photon ionization REMPI ... of the organic molecules which are favorable for a photoionization method have ionization potentials ... nm . Characteristics APLI has some special characteristics because of the ionization with UV laser ... trough UV transparent windows. Selectivity APLI is s selective ionization method, because the 1 1 REMPI ionization requires an adequate existing electronic intermediate state and both electronic ... the spectroscopic requirements for 1 1 REMPI, thus APLI is an ideal ionization method for the detection ... a disadvantage, if the direct ionization of an analyte molecule is not possible with APLI. In this case ... sections of Nitrogen, Oxygen and some common LC Solvents at the ionization energies of APPI 10 ... more details
Electron capture ionization is the ionization of a gas phase atom or molecule by attachment of an electron to create an ion of the form A sup sup . The reaction is math A e overset M to A math where the M over the arrow denotes that to conserve energy and momentum a third body is required the molecularity of the reaction is three . Electron capture can be used in conjunction with chemical ionization . ref Citation doi 10.1021 ac50035a017 title Electron capture negative ion chemical ionization mass spectrometry year 1978 author Donald F. Hunt Frank W. Crow journal Analytical Chemistry volume 50 issue 13 pages 1781 ref An electron capture detector is used in some gas chromatography systems. ref GoldBookRef title electron capture detector in gas chromatography file E01981 ref See also Electron capture dissociation References Reflist analytical chem stub Category Ion source ... more details
Infobox chemical analysis name Atmospheric pressure chemical ionization image Apci.gif caption Atmospheric pressure chemical ionization interface acronym APCI classification Mass spectrometry analytes Organic molecule s br Biomolecule s related Chemical ionization br Electrospray hyphenated Liquid chromatography mass spectrometry Atmospheric pressure chemical ionization APCI is an Ion source ionization method used in mass spectrometry . It is a form of chemical ionization which takes place at atmospheric pressure. ref name pmid17405144 cite journal author Prakash C, Shaffer CL, Nedderman A title Analytical strategies for identifying drug metabolites journal Mass Spectrometry Reviews volume 26 issue 3 pages 340 69 year 2007 pmid 17405144 doi 10.1002 mas.20128 ref How it works APCI allows for the high flow rates typical of standard bore High performance liquid chromatography HPLC to be used directly, often without diverting the larger fraction of volume to waste. Typically the mobile phase containing eluting analyte is heated to relatively high temperatures above 400 degrees Celsius , sprayed with high flow rates of nitrogen and the entire aerosol cloud is subjected to a corona discharge that creates ion s. Often APCI can be performed in a modified electrospray ionisation ESI source. The ionization occurs in the gas phase, unlike ESI, where the ionization occurs in the liquid phase. A potential advantage of APCI is that it is possible to use a nonpolar solvent as a mobile phase solution, instead of a polar solvent, because the solvent and molecules of interest are converted to a gaseous state before reaching the corona discharge pin. Typically, APCI is a less soft ionization technique than ESI, i.e. it generates more fragment ions relative to the parent ion. ref name pmid16723751 cite journal author Zaikin VG, Halket JM title Derivatization in mass spectrometry 8. Soft ionization mass spectrometry of small molecules journal European Journal of Mass Spectrometry volume ... more details
Sonic spray ionization SSI is a method for creating ion s from a liquid solution , for example, a mixture of methanol and water . A pneumatic nebulizer is used to turn the solution into a supersonic spray of small droplets. Ions are formed when the solvent evaporate s and the statistically unbalanced charge distribution on the droplets leads to a net charge. Complete desolvation results in ions that can be detected using mass spectrometry . ref name pmid8779414 cite journal author Hirabayashi A, Sakairi M, Koizumi H title Sonic spray mass spectrometry journal Anal. Chem. volume 67 issue 17 pages 2878 2882 year 1995 pmid 8779414 doi 10.1021 ac00113a023 ref Applications Sonic spray ionization has been coupled with high performance liquid chromatography for the analysis of drugs. ref name pmid11908800 cite journal author Arinobu T, Hattori H, Seno H, Ishii A, Suzuki O title Comparison of SSI with APCI as an interface of HPLC mass spectrometry for analysis of a drug and its metabolites journal J. Am. Soc. Mass Spectrom. volume 13 issue 3 pages 204 208 year 2002 pmid 11908800 doi 10.1016 S1044 0305 01 00359 2 ref ref name pmid12141684 cite journal author Dams R, Benijts T, G nther W, Lambert W, De Leenheer A title Sonic spray ionization technology performance study and application to a LC ... with a sonic spray ionization source journal Anal Sci volume 17 issue 10 pages 1179 1182 year ... M, Hirabayashi A title Multi charged oligonucleotide ion formation in sonic spray ionization journal ... SSI has been used in a manner similar to desorption electrospray ionization ref name pmid16941547 cite journal author Haddad R, Sparrapan R, Eberlin MN title Desorption sonic spray ionization for high ... 2901 2905 year 2006 pmid 16941547 doi 10.1002 rcm.2680 ref for ambient ionization and has been couplet ... R, Milagre HM, Catharino RR, Eberlin MN title Easy Ambient Sonic Spray Ionization Mass Spectrometry ... chemical ionization References Reflist Category Ion source analytical chem stub ... more details
Unreferenced stub auto yes date December 2009 A discharge ionization detector DID is a type of detector used in gas chromatograph y. Principle A DID is an GC ion detector ion detector which uses a high voltage electric discharge to produce ion s. The spark ionizes helium atoms that are mixed with components as they elute from the gas chromatograph GC s column, causing the components to become ionized. The ion s produce an electric current , which is the signal information theory signal output of the detector. The greater the concentration of the component, the more ions are produced, and the greater the current. Application DIDs are sensitive to a broad range of components. DIDs are non destructive detectors. They do not destroy consume the components they detect. Therefore they can be used before other detectors in multiple detector configurations. DIDs are an improvement over Helium ionization detector s in that they contain no radioactive source.Figure should be included. DEFAULTSORT Discharge Ionization Detector Category Gas chromatography Analytical chemistry stub ... more details
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