Image Chlorate 3D vdW.png thumb right 200px The chlorate ion Image Chlorate 2D.png thumb right 200px Structure and bonding in the chlorate ion The chlorate anion has the formula ClO su b 3 p . In this case, the chlorine atom is in the 5 oxidation state . Chlorate can also refer to chemical compound s containing this anion Chlorate Compounds salts chlorates are the salt chemistry salt s of chloric acid . Chlorate , when followed by a roman numeral in parentheses, e.g. chlorate VII , refers to a particular Chlorate Other oxyanions oxyanion of chlorine . As predicted by VSEPR , chlorate anions have trigonal pyramid chemistry trigonal pyramidal structures . Chlorates are powerful oxidation oxidizers and should be kept away from organics or easily oxidized materials. Mixtures of chlorate salts with virtually any combustible material sugar, sawdust, charcoal, organic solvents, metals, etc. will readily deflagrate . Chlorates were once widely used in pyrotechnics for this reason, though their use has fallen due to their instability. Most pyrotechnic applications which formerly used chlorates in the past now use the more stable perchlorate s instead. See also Category Chlorates TOC Structure and bonding The chlorate ion cannot be satisfactorily represented by just one Lewis structure , since all the Cl O bonds are the same length 1.49 in potassium chlorate ref cite journal journal Acta Cryst. year 1981 volume B37 pages 913 915 title The structure of potassium chlorate at 77 and 298 K author J. Danielsen, A. Hazell, F. K. Larsen doi 10.1107 S0567740881004573 ref , and the chlorine atom is Hypervalent molecule hypervalent . Instead, it is often thought of as a hybrid of multiple Resonance chemistry resonance structures File Chlorate resonance 2D.png 400px Resonance structures of the chlorate ion Preparation Laboratory Metal chlorates can be prepared by adding chlorine to hot metal hydroxide s like Potassium hydroxide KOH 3 Cl sub 2 sub 6 KOH 5 KCl KClO sub 3 sub 3 H su ... more details
Prism polyhedra db Prism polyhedron stat table AP4 In geometry , the square antiprism is the second in an infinite set of antiprism s formed by an even numbered sequence of triangle sides closed by two polygon caps. It is also known as an anticube . ref Holleman Wiberg. Inorganic Chemistry , Academic Press, Italy, p. 299. ISBN 0 12 352651 5. ref If all its faces are regular, it is a semiregular polyhedron . When eight points are distributed on the surface of a sphere with the aim of maximising the distance between them in some sense, then the resulting shape corresponds to a square anti prism rather than a cube geometry cube . Different examples include maximising the distance to the nearest point, or using electrons to maximise the sum of all reciprocals of squares of distances. Molecules with square antiprism geometry According to the VSEPR theory of molecular geometry in chemistry, which is based on the general principle of maximizing the distances between points, a square antiprism is a favoured geometry when eight pairs of electrons surround a central atom. One molecule with this geometry is the octafluoroxenate VI ion XeF sub 8 sub sup 2 sup in the salt nitrosonium octafluoroxenate VI however, the molecule is distorted away from the idealized square antiprism. ref name peterson cite doi 10.1126 science.173.4003.1238 ref In addition, the element sulfur forms octatomic S sub 8 sub molecules as its most stable allotrope. The S sub 8 sub molecule has a structure based on the square antiprism, in which the eight atoms occupy the eight vertices of the antiprism, and the eight triangle triangle edges of the antiprism correspond to single covalent bonds between sulfur atoms. Related polyhedra As an antiprism , the square antiprism belongs to a family of polyhedra that includes the octahedron which can be seen as a triangle capped antiprism , the pentagonal antiprism , the hexagonal antiprism , and the octagonal antiprism . The gyroelongated square pyramid is a Jo ... more details
and molecule shape Hybridisation, along with the VSEPR theory , helps to explain molecule shape ... of the oxygen in water is described as sp sup 3 sup following the guidelines of VSEPR and the tetrahedral ... 31G basis set with d functions, compared to the expermimental 104.5 . ref Thus while VSEPR and its ... more details
chembox verifiedrevid 445419652 Name Oxygen difluoride ImageFile Oxygen difluoride 2D.png ImageSize 160px ImageName Structure and dimensions of the oxygen difluoride molecule ImageFile1 Oxygen difluoride 3D vdW.png ImageSize1 160px ImageName1 Space filling model of the oxygen difluoride molecule OtherNames difluorine monoxide br fluorine monoxide br oxygen fluoride br hypofluorous anhydride Section1 Chembox Identifiers ChemSpiderID Ref chemspidercite correct chemspider ChemSpiderID 22953 InChI 1 F2O c1 3 2 InChIKey UJMWVICAENGCRF UHFFFAOYAI ChEBI Ref ebicite correct EBI ChEBI 30494 SMILES FOF StdInChI Ref stdinchicite correct chemspider StdInChI 1S F2O c1 3 2 StdInChIKey Ref stdinchicite correct chemspider StdInChIKey UJMWVICAENGCRF UHFFFAOYSA N CASNo Ref cascite correct ?? CASNo 7783 41 7 PubChem 24547 RTECS RS2100000 Section2 Chembox Properties Formula OF sub 2 sub Appearance colorless gas, pale yellow liquid when condensed Odor peculiar, foul odor MolarMass 53.9962 g mol Density 1.9 g cm sup 3 sup as liquid at 145 C Solvent other solvents SolubleOther 68 mL gaseous OF sub 2 sub in 1 L 0 C ref Yost, D. M. Oxygen Fluoride Inorganic Syntheses, 1939 volume, 1, pages 109 111. ref MeltingPtC 223.8 BoilingPtC 144.75 Section4 Chembox Thermochemistry DeltaHf 24.5 kJ mol sup 1 sup Section8 Chembox Related OtherCpds Hypofluorous acid HFO br Dioxygen difluoride O sub 2 sub F sub 2 sub br difluoramine NHF sub 2 sub br Nitrogen trifluoride NF sub 3 sub br Sulfur dichloride SCl sub 2 sub Oxygen difluoride is the chemical compound with the chemical formula formula OF sub 2 sub . As predicted by VSEPR theory , the molecule adopts a V shaped structure like water H sub 2 sub O , but it has very different properties, being a strong oxidizer . Preparation Oxygen difluoride was first reported in 1929 it was obtained by the electrolysis of molten potassium fluoride and hydrofluoric acid containing small quantities of Water molecule water . ref Paul Lebeau Damiens, A. A New Method for t ... more details
chembox Watchedfields changed verifiedrevid 446242167 Name Iodine heptafluoride ImageFile Iodine heptafluoride 2D dimensions.png ImageSize 120px ImageName Structure of the iodine heptafluoride molecule ImageFileL1 Iodine heptafluoride 3D balls.png ImageSizeL1 120px ImageNameL1 Iodine heptafluoride ImageFileR1 Iodine heptafluoride 3D vdW.png ImageSizeR1 120px ImageNameR1 Iodine heptafluoride OtherNames iodine fluoride br heptafluoroiodine Section1 Chembox Identifiers InChI 1 F7I c1 8 2,3,4,5,6 7 InChIKey XRURPHMPXJDCOO UHFFFAOYAO SMILES FI F F F F F F StdInChI Ref stdinchicite correct chemspider StdInChI 1S F7I c1 8 2,3,4,5,6 7 StdInChIKey Ref stdinchicite correct chemspider StdInChIKey XRURPHMPXJDCOO UHFFFAOYSA N CASNo Ref cascite correct ?? CASNo 16921 96 3 ChemSpiderID Ref chemspidercite correct chemspider ChemSpiderID 21477354 PubChem 85645 Section2 Chembox Properties Formula IF sub 7 Appearance colorless gas MolarMass 259.90 g mol Density 2.6 g cm sup 3 sup 6 C br 2.7 g cm sup 3 sup 25 C Solubility soluble ref Pradyot Patnaik. Handbook of Inorganic Chemicals . McGraw Hill, 2002, ISBN 0070494398 ref MeltingPt 4.5 C triple point BoilingPt 4.8 C sublimes at 1 atm Section3 Chembox Related OtherCpds iodine pentafluoride Iodine heptafluoride , also known as iodine VII fluoride or even iodine fluoride, is an interhalogen compound with chemical formula iodine I fluoride F sub 7 sub . ref Macintyre, J. E. Ed. . 1992 . Dictionary of Inorganic Compounds Vol. 3 . London Chapman & Hall. ref ref O Neil, Maryadele J. Ed. . 2001 . The Merck Index 13th ed. . Whitehouse Station, NJ Merck. ref It has an unusual Pentagonal bipyramid molecular geometry pentagonal bipyramidal structure, as predicted by VSEPR theory . ref cite journal title On the problem of heptacoordination vibrational spectra, structure, and fluxionality of iodine heptafluoride author K. O. Christe, E. C. Curtis, D. A. Dixon journal Industrial & Engineering Chemistry year 1993 volume 115 issue 4 pages 1520 1526 doi ... more details
Image Ch4 structure.png thumb right 200px The tetrahedral molecule methane CH sub 4 sub In a tetrahedral molecular geometry a central atom is located at the center with four substituent s that are located at the corners of a tetrahedron . The bond angle s are cos sup nowiki &minus nowiki 1 sup nowiki &minus nowiki 1 3 109.5 when all four substituents are the same, as in methane CH sub 4 sub . This molecular geometry is common throughout the first half of the periodic table. The perfectly symmetrical tetrahedron belongs to point group T sub d sub , but most tetrahedral molecules are not of such high symmetry. Tetrahedral molecules can be Chirality chemistry chiral . Examples Main group chemistry Aside from virtually all saturated organic compounds, most compounds of Si, Ge, and Sn are tetrahedral. Often tetrahedral molecules feature multiple bonding to the outer ligands, as in xenon tetroxide XeO sub 4 sub , the perchlorate ion ClO sub 4 sub sup nowiki &minus nowiki sup , the sulfate ion SO sub 4 sub sup 2 nowiki &minus nowiki sup , the phosphate ion PO sub 4 sub sup 3 nowiki &minus nowiki sup . Thiazyl trifluoride , SNF sub 3 sub is tetrahedral, featuring a sulfur to nitrogen triple bond. ref cite book author G. L. Miessler and D. A. Tarr title Inorganic Chemistry edition 3rd publisher Pearson Prentice Hall isbn 0 13 035471 6 ref Ammonia can be classified as tetrahedral, if one considers the lone pair as a ligand as in the language of VSEPR theory. The H N H angles are 107 , being contracted from 109.4 , a difference attributed to the influence of the lone pair. Ammonia is actually classified as pyramidal as nonbonding electron pairs have a greater repulsive influence. Transition metal chemistry Again the geometry is widespread, particularly so for complexes where the metal has d sup 0 sup or d sup 10 sup configuration. Illustrative examples include tetrakis triphenylphosphine palladium 0 , nickel carbonyl , and titanium tetrachloride . Many complexes with incomplet ... more details
chembox verifiedrevid 402675897 Name Strontium fluoride ImageFile Fluorite unit cell 3D ionic.png ImageSize 200px ImageName strontium fluoride OtherNames Strontium difluoride br Strontium II fluoride Section1 Chembox Identifiers ChemSpiderID Ref chemspidercite correct chemspider ChemSpiderID 74190 InChI 1 2FH.Sr h2 1H q 2 p 2 InChIKey FVRNDBHWWSPNOM NUQVWONBAO SMILES Sr 2 . F . F StdInChI Ref stdinchicite correct chemspider StdInChI 1S 2FH.Sr h2 1H q 2 p 2 StdInChIKey Ref stdinchicite correct chemspider StdInChIKey FVRNDBHWWSPNOM UHFFFAOYSA L CASNo 7783 48 4 CASNo Ref cascite correct CAS EINECS 232 00 3 PubChem 82210 Section2 Chembox Properties Formula SrF sub 2 sub MolarMass 125.62 g mol Density 4.24 g cm sup 3 sup Solubility 0.039 g 100 mL MeltingPt 1477 C BoilingPt 2460 C RefractIndex 1.439 0.58 m Section3 Chembox Structure CrystalStruct cubic crystal system , pearson symbol cF12 SpaceGroup Fm u style text decoration overline 3 u m, 225 Coordination Sr, 8, cubic br F, 4, tetrahedral Section7 Chembox Hazards ExternalMSDS EUIndex Not listed FlashPt Non flammable Section8 Chembox Related OtherAnions Strontium chloride br Strontium bromide br Strontium iodide OtherCations beryllium fluoride br magnesium fluoride br calcium fluoride br barium fluoride Strontium fluoride , SrF sub 2 sub , also called strontium difluoride and strontium II fluoride , is a fluoride of strontium . It is a stable brittle white crystalline solid with melting point of 1477 C and boiling point 2460 C. Preparation Strontium fluoride is prepared by reaction of strontium chloride with fluorine gas, or by action of hydrofluoric acid on strontium carbonate . Structure The solid adopts the calcium fluoride fluorite structure. In the vapour phase the SrF sub 2 sub molecule is non linear with an F Sr F angle of approximately 120 . ref name Greenwood Greenwood&Earnshaw ref This is an exception to VSEPR theory which would predict a linear structure. Ab initio calculations have been cited to propose tha ... more details
Localized molecular orbitals are molecular orbital s which are concentrated in a limited spatial region of a molecule, for example a specific bond or a lone pair on a specific atom. They can be used to relate molecular orbital calculations to simple bonding theories, and also to speed up post Hartree Fock electronic structure calculations by taking advantage of the local nature of electronic correlation electron correlation . Standard ab initio quantum chemistry methods lead to delocalized orbitals which in general extend over an entire molecule and have the symmetry of the molecule. Localized orbitals may then be found as linear combination s of the delocalized orbitals, given by an appropriate unitary transformation . In the water molecule for example, ab initio calculations show bonding character primarily in two molecular orbitals, each with electron density equally distributed among the two O H bonds. The localized orbital corresponding to one O H bond is the sum of these two delocalized orbitals, and the localized orbital for the other O H bond is their difference. Similarly, molecular orbital calculations show two nonbonding valence shell orbitals a roughly sp sup 2 sup hybrid orbital in the plane of the molecule and a pure p orbital perpendicular to this plane. The tetrahedral sp sup 3 sup hybrids of valence bond theory and the electron pairs of VSEPR theory can be compared to the sum and the difference of these nonbonding orbitals. Equivalence of localized and delocalized orbital descriptions For molecules with a closed electron shell, in which each molecular orbital is doubly occupied, the localized and delocalized orbital descriptions are in fact equivalent and represent the same physical state. It might seem, again using the example of water, that placing two electrons in the first bond and two other electrons in the second bond is not the same as having four electrons free to move over both bonds. However in quantum mechanics all electrons are identical ... more details
File Electron localization function of Kr HF cc pV5Z .png thumb right 350px Electron localization function of the krypton atom at the Hartree Fock cc pV5Z level of theory. Also shown is the radial electronic density density , 4&pi r sup 2 sup &rho r , scaled by a factor of 0.0375. In quantum chemistry , the electron localization function ELF is a measure of the likelihood of finding an electron in the neighborhood space of a reference electron located at a given point and with the same spin. Physically, this measures the extent of spatial localization of the reference electron and provides a method for the mapping of electron pair probability in multielectronic systems. ELF s usefulness stems from the manner it allows the analysis of electron localization in a chemically intuitive way. For example, the shell structure of heavy atoms is obvious when plotting ELF against the radial distance from the nucleus the ELF for radon, for example, has six clear maxima, whereas the electronic density decreases monotonically and the radially weighted density fails to show all shells. When applied to molecules, an analysis of the ELF shows a clear separation between the core and valence electron, and also shows covalent bond s and lone pair s, in what has been called a faithful visualization of VSEPR theory in action . Another feature of the ELF is that it is invariant with respect to transformation of the molecular orbital s. File Elf h2o.png thumb right 250px Image of the ELF of water at level 0.8, generated using PyMOL The ELF was originally defined by Axel D. Becke and K. E. Edgecombe in 1990. ref cite journal last A. D. Becke and K. E. Edgecombe year 1990 title A simple measure of electron localization in atomic and molecular systems journal J. Chem. Phys. volume 92 pages 5397&ndash 5403 doi 10.1063 1.458517 first1 A. D. last2 Edgecombe first2 K. E. ref They first argued that a measure of the electron localization is provided by math D sigma mathbf r tau sigma ma ... more details
Chembox verifiedrevid 432357218 Reference ref name EROS http www.mrw.interscience.wiley.com eros articles rp071 abstract fs.html Phenyliodine III Dichloride , David W. Knight and Glen A. Russell, in Encyclopedia of Reagents for Organic Synthesis , 2001, John Wiley & Sons, Ltd DOI 10.1002 047084289X.rp071 ref ImageFileL1 PhICl2 2D skeletal with explicit lone pair stereochemistry.png ImageSizeL1 100px ImageAltL1 ImageFileR1 PhICl2 from xtal 1996 3D CM balls.png ImageSizeR1 120px ImageAltR1 IUPACName Dichloro &lambda sup 3 sup iodanyl benzene OtherNames Iodosobenzene dichloride Phenyliodine III dichloride Phenyliodo dichloride Phenyliodoso chloride Phenylchloroiodonium chloride Dichloroiodobenzene Iododichlorobenzene Section1 Chembox Identifiers Abbreviations IBD CASNo Ref cascite correct ?? CASNo 932 72 9 PubChem SMILES ClI Cl C1 CC CC C1 Section2 Chembox Properties C 6 H 5 I 1 Cl 2 MolarMass Appearance Yellow solid Density 2.2 g cm sup 3 sup MeltingPt 115 120 C dec. BoilingPt Solubility Section3 Chembox Hazards MainHazards FlashPt Autoignition Iodobenzene dichloride PhICl sub 2 sub is a complex of iodobenzene with chlorine . It is used as an oxidant . Single crystal X ray crystallography has been used to determine its structure as can be predicted by VSEPR theory , it adopts a T shaped geometry about the central iodine atom. ref cite journal journal Acta Cryst. year 1953 volume 6 pages 88 92 doi 10.1107 S0365110X53000193 title The crystal structure of benzene iododichloride author E. M. Archer and T. G. van Schalkwy ref ref cite journal author J. V. Carey, P. A. Chaloner, P. B. Hitchcock, T. Neugebauer, K. R. Seddon journal Journal of Chemical Research J. Chem. Res. year 1996 volume 358 pages 2031&ndash ref Preparation Iodobenzene dichloride is not stable, and is not commonly available commercially. It is prepared by passing chlorine gas through a solution of iodobenzene in chloroform , from which it precipitates. ref OrgSynth title Iodobenzene dichloride author H. J ... more details
spatial arrangement of atoms after the sphericity of single atoms. ref name qpxlgb VSEPR A Summary . University of Berkeley College of Chemistry. 20 January 2008. http mc2.cchem.berkeley.edu VSEPR ... more details
or absence of paramagnetism . br VSEPR may be used for complexes of main group element to predict ... Molecular geometry VSEPR Ligand field theory The cis effect Addition to pi ligands References reflist ... more details
and interviews. Local artists that have performed on air include Erik Koskinen, VSEPR, the Lumber ..., Fried Chinese Donalds, Old Victoria, Nobody Likes a Tricycle, VSEPR, and the Pisst Off Androids. Citation ... more details
Image Styrene polymerization.png thumb right 200px An example of alkene polymerization , in which each Styrene monomer unit s double bond reforms as a single bond with another styrene monomer and forms polystyrene . In polymer chemistry , polymerization is a process of reacting monomer molecule s together in a chemical reaction to form polymer chains or three dimensional networks. ref Introduction to Polymers 1987 R.J. Young Chapman & Hall ISBN 0 412 22170 5 ref ref http goldbook.iupac.org P04740.html International Union of Pure and Applied Chemistry, et al. 2000 IUPAC Gold Book , Polymerization ref ref Clayden, J., Greeves, N. et al. 2000 . Organic chemistry Oxford ref There are many forms of polymerization and different systems exist to categorize them. Introduction align right class infobox style text align center div style font size 14px font weight bold Homopolymers div math A A A... rightarrow AAA ... math div style font size 14px font weight bold Copolymers div math A B A... rightarrow ABA ... math In chemical compounds, polymerization occurs via a variety of reaction mechanisms that vary in complexity due to functional group s present in reacting compounds ref name clayden organic Clayden, J., Greeves, N. et al. 2000 , p1450 1466 ref and their inherent steric effects explained by VSEPR Theory . In more straightforward polymerization, alkenes , which are relatively stable due to math sigma math chemical bonding bonding between carbon atoms, form polymers through relatively simple radical reactions in contrast, more complex reactions such as those that involve substitution at the carbonyl group require more complex synthesis due to the way in which reacting molecules polymerize. ref name clayden organic As alkenes can be formed in somewhat straightforward reaction mechanisms, they form useful compounds such as polyethylene and polyvinyl chloride PVC when undergoing radical reactions, ref name clayden organic which are produced in high tonnages each year ref na ... more details
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