Valence shell electron pair repulsion VSEPR rules are a model abstract model in chemistry used to predict .... The acronym VSEPR is sometimes pronounced vesper for ease of pronunciation however, the phonetic ... page 119 ref The premise of VSEPR is that the valence chemistry valence electron pairs surrounding ..., both bonding and nonbonding, is called its steric number . VSEPR theory is usually compared and contrasted ... into molecules and polyatomic ions. VSEPR theory has long been criticized for not being ... fields based on VSEPR have also been developed. ref cite journal last Box first Vernon G. S. title ... R.J.Gillespie, J.Chem.Educ. 47, 18 1970 ref Description The VSEPR rules mainly involve predicting the layout ... protruding and projecting bonds. Where two or more resonance structure s can depict a molecule, the VSEPR model is applicable to any such structure. For the purposes of VSEPR theory, the multiple electron ... counting is commonly used when applying the VSEPR theory. The A represents the central atom ... bond theory. Based on the steric number and distribution of X & 39 s and E & 39 s, VSEPR theory ... to one of the square faces of the square antiprism. Exceptions There are groups of compounds where VSEPR ... that predicted by VSEPR. Many transition metal compounds do not have the geometries predicted by VSEPR ... Housecroft2004 Housecroft2nd ref VSEPR and localized orbitals The VSEPR theory places each pair of valence ... other, which can be compared to the lone pairs of VSEPR theory. Likewise, there are two calculated bonding ... Molecular Structure Center DEFAULTSORT Vsepr Theory Category Chemistry theories Category Molecular geometry Category Stereochemistry Category Quantum chemistry ca Teoria RPECV cs Teorie VSEPR de VSEPR Modell es TREPEV fa fr Th orie VSEPR ko id Teori VSEPR it Teoria VSEPR he VSEPR nl Valentieschil elektronenpaar repulsie theorie ja pl VSEPR ru scn Tiur a VSEPR sv VSEPR teorin th ... more details
Orphan date May 2011 The Kepert model is a modification of VSEPR theory used to predict the 3 dimensional structures of transitional metal complexes. In the Kepert model the ligands attached to the metal are considered to repel each other the same way that point charges repel each other in VSEPR theory. Unlike VSEPR theory, the Kepert model does not account for non bonding electrons. Therefore, the geometry of the coordination complex is independent of the electronic configuration of the metal center. Thus ML sub n sub sup m sup has the same coordination geometry as ML sub n sub sup m sup . The Kepert model predicts the following geometries for coordination numbers of 2 through 6 2 linear 3 trigonal planar 4 tetrahedral 5 trigonal bipyramidal or square pyramidal 6 octahedral Category Chemistry theories ... more details
The term bent bond generally refers to any form of bond in a structure that resembles the shape of a banana, but may also refer to Bent molecular geometry in VSEPR Theory and molecular geometry, a structure which contains one or two lone pairs. Rarely, in Thermodynamics , as the application of heat to a system contributing towards the breaking of bonds. disambig ... more details
Image Sulfur tetrafluoride 2D dimensions.png thumb Sulfur tetrafluoride has a steric number of 5. The steric number of a molecule is the number of atoms bonded to the central atom of a molecule plus the number of lone pairs on the central atom. It is often used in VSEPR theory valence shell electron pair repulsion theory in order to determine the particular shape, or molecular geometry , that will be formed. Steric number in VSEPR Calculating the steric number of a molecule s central atom is a vital step in figuring out its geometry. On the molecule Sulfur tetrafluoride SF sub 4 sub , for example, the central sulfur atom has four ligands about it, calculated by considering sulfur s coordination number . In addition to the four ligands, sulfur also has one remaining lone pair expanded octet does not apply in this compound . Thus, the steric number is 5. Comparing a central atom s steric number to the number of ligands not counting lone pairs allows one to figure out the geometry of that central atom. See also AXE method Stereochemistry Category Stereochemistry Category Molecular geometry chemistry stub ko it Numero sterico ... more details
4 sub sup sup 212 130 109.5 PF sub 3 sub 237 157 97.8 PF sub 4 sub sup sup 238 145.7 109.5 LCP and VSEPR LCP and VSEPR make very similar predictions as to geometry but LCP theory has the advantage that predictions ... more details
Ronald James Gillespie , Post nominals country CAN CM FRSC born August 21, 1924 , a chemistry professor at McMaster University , specializes in the field of Molecular Geometry in Chemistry. In 2007 he was awarded the Order of Canada . ref OCC 10558 ref He was educated at the University of London obtaining a B.Sc in 1945, a Ph.D in 1949 and a D.Sc in 1957. He was Assistant Lecturer and then Lecturer in the Department of Chemistry at University College London in England from 1950 to 1958. He moved to McMaster University , Hamilton, Ontario , Canada in 1958 and is now emeritus professor. He was elected as a Fellow of the Royal Society of Canada in 1965 and a Fellow of the Royal Society of London in 1977. Gillespie has done extensive work on expanding the idea of the VSEPR Valence Shell Electron Pair Repulsion VSEPR model of Molecular Geometry, which he developed with Sir Ronald Sydney Nyholm Ronald Nyholm , and setting the rules for assigning numbers. He has written several books on this VSEPR topic in chemistry . With other workers he developed LCP theory , ligand close packing theory , which for some molecules allows geometry to be predicted on the basis of ligand ligand repulsions. Gillespie has also done extensive work on interpreting the covalent radius of fluorine . The covalent radius of most atoms is found by taking half the length of a single bond between two similar atoms in a neutral molecule. Calculating the covalent radius for fluorine is more difficult because of its high electronegativity compared to its small atomic radius size. Ronald Gillespie s work on the bond length of fluorine focuses on theoretically determining the covalent radius of fluorine by examining its covalent radius when it is attached to several different atoms. ref cite journal author E. A. Robinson title The career and scientific work of Ronald J. Gillespie an appreciation and overview journal Coord. Chem. Rev. volume 197 issue 1 pages 3 19 year 2000 doi 10.1016 S0010 8545 99 00187 3 ... more details
Image Bent 3D balls.png thumb left 200px Idealised structure of a molecule with the bent coordination geometry. Image Oxygen difluoride 3D vdW.png thumb right 200px Oxygen difluoride , an example of a molecule with the bent coordination geometry. In chemistry , the term bent can be applied to certain molecule s to describe their molecular geometry . H sub 2 sub O is an example of a bent molecule. The bond angle between the two hydrogen atoms is approximately 104.45 . ref G. L. Miessler and D. A. Tarr Inorganic Chemistry 3rd Ed, Pearson Prentice Hall publisher, ISBN 0 13 035471 6. ref Nonlinear triatomic molecules and ions are common for compounds containing only main group elements, prominent examples being nitrogen dioxide , Sulfur dichloride SCl sub 2 sub , and the Carbene CH sub 2 sub . This geometry is almost always consistent with VSEPR theory . See also AXE method Molecular geometry References reflist External links http www.3dchem.com 3D Chem Chemistry, Structures, and 3D Molecules http www.iumsc.indiana.edu Indiana University Molecular Structure Center http www.phys.ncl.ac.uk staff njpg symmetry Molecules l3d.html Point Group Symmetry Interactive Examples http chemlab.truman.edu CHEM121Labs MolecularModeling1.htm Molecular Modeling http intro.chem.okstate.edu 1314F97 Chapter9 3BP.html Animated Trigonal Planar Visual MolecularGeometry Category Stereochemistry Category Molecular geometry es Geometr a molecular angular nl Gebogen moleculaire geometrie ja sv B jd geometri ... more details
Image Square pyramidal 3D balls.png thumb left 200px Idealized structure of a compound with square pyramidal coordination geometry. Image Xenon oxytetrafluoride 3D vdW.png thumb right 200px Structure of xenon oxytetrafluoride , an example of a molecule with the square pyramidal coordination geometry. In molecular geometry , square based pyramidal geometry describes the shape of certain compounds with the formula ML sub 5 sub where L is a ligand . If the ligand atoms were connected, the resulting shape would be that of a pyramid with a square base. The geometry is common for certain main group compounds that have a stereochemically active lone pair, as described by VSEPR theory . Certain compounds crystallize in both the trigonal bipyramidal and the square pyramidal structures, notably Ni CN sub 5 sub sup 3 sup . ref cite journal last1 Spiro first1 Thomas G. last2 Terzis first2 Aristides last3 Raymond first3 Kenneth N. doi 10.1021 ic50093a006 title Structure of Ni CN sub 5 sub sup 3 sup . Raman, infrared, and x ray crystallographic evidence year 1970 pages 2415 volume 9 journal Inorg. Chem. issue 11 ref As a transition state in Berry Pseudorotation As a trigonal bipyramidal molecule undergoes Berry pseudorotation , it proceeds via an intermediary stage with the square planar geometry. Thus even though the geometry is rarely seen as the ground state, it is accessed by a low energy distortion from a trigonal bipyramid. Pseudorotation also occurs in square pyramidal molecules. Molecules with this geometry, as opposed to trigonal bipyramidal, exhibit heavier vibration. The mechanism used is similar to the Berry mechanism. Examples Some molecular compounds that adopt square pyramidal geometry are XeOF sub 4 sub , ref Square Pyramidal Molecular Geometry . VSEPR. http www.up.ac.za academic chem mol geom planpyr.htm ref and XF sub 5 sub X Cl, Br, I also have square pyramidal geometries. ref Square Pyramidal Geometry . http intro.chem.okstate.edu 1314F97 Chapter9 5BP1LP.html ... more details
Chembox Name Xenon dioxide ImageFile Xenon dioxide 2D.png ImageSize 250px IUPACName xenon dioxide Section1 Chembox Identifiers CASNo 12340 14 6 Section2 Chembox Properties Formula XeO sub 2 sub MolarMass 163.29 g mol Appearance Density Solubility MeltingPt BoilingPt pKa Section1 Chembox Structure MolShape Square planar molecular geometry Square planar Dipole Section4 Chembox Thermochemistry DeltaHf Entropy Section7 Chembox Hazards EUClass Section8 Chembox Related OtherCpds Xenon trioxide br Xenon tetroxide Xenon dioxide , or xenon IV oxide , is a compound of xenon and oxygen with formula XeO sub 2 sub , which was synthesized in 2011. It is synthesized at 0 C by hydrolysis of xenon tetrafluoride in water with 2.00 mol L H sub 2 sub SO sub 4 sub . ref cite journal doi 10.1021 ja110618g title Synthesis of the Missing Oxide of Xenon, XeO2, and Its Implications for Earth s Missing Xenon year 2011 last1 Brock first1 David S. last2 Schrobilgen first2 Gary J. journal Journal of the American Chemical Society volume 133 issue 16 pages 6265 6269 pmid 21341650 ref It has an extended chain or network structure in which xenon and oxygen have coordination number s of four and two respectively. The geometry at xenon is square planar , consistent with VSEPR theory for four ligands and two lone pairs or AX sub 4 sub E sub 2 sub in the notation of VSEPR theory . In addition, the existence of an XeO sub 2 sub molecule was predicted by an ab initio quantum chemistry method several years earlier by Pyykk and Tamm, but these authors did not consider an extended structure. ref cite journal last Pyykk first Pekka coauthors Tamm, Toomas title Calculations for XeO sub n sub n 2 4 Could the Xenon Dioxide Molecule Exist? journal The Journal of Physical Chemistry A date 1 April 2000 volume 104 issue 16 pages 3826 3828 doi 10.1021 jp994038d ref References references Xenon compounds Noble gas compounds Category Oxides Category Xenon compounds Category Inorganic compounds fa ja ... more details
Vesper means evening in Classical Latin . It can refer to Hesperus , Latinized form of Hesperos, a Greek mythological figure Roman Vesper Places Vesper, Wisconsin , a village Vesper Peak , a mountain in Washington State Vesper, an abandoned village southwest of Swift Current, Saskatchewan , Canada People Rose Vesper , member of the Ohio House of Representatives 1993 2000 Will Vesper 1882 1962 , German author and literary critic Rudolf Vesper born 1939 , East German Olympic gold medalist in Greco Roman wrestling In fiction Vesper comics , a female mutant in the Marvel Comics universe Vesper novel Vesper novel , a young adult novel by Jeff Sampson Vesper Holly , a character from a book series by Lloyd Alexander Vesper Lynd , a character in the James Bond novel and film Casino Royale Vesper, an organization in the manga and anime series Mahoromatic Vesper Family, a family in the book series The 39 Clues Vesper Family The 39 Clues In science Vesper bat , the largest, best known family of bats Vesper mouse , a rodent genus Vesper Sparrow , a medium sized bird Vesper mission, a planned Venus chemistry and dynamics orbiter of the NASA Discovery Program Other Vesper Boat Club , an amateur rowing club in Philadelphia, Pennsylvania Vesper Country Club , one of the first golf courses in the United States Vesper cocktail , a martini style alcoholic beverage recipe created by Ian Fleming Sicilian Vespers , a rebellion against Charles I s rule on Sicily in 1282. See also Vespers disambiguation Vespa VSEPR theory in chemistry, often pronounced Vesper disambig de Vesper fr Vesper nl Vesper pl Vesper fi Vesper ... more details
File Prochirality V.1.svg thumb An sp sup 2 sup hybridized carbon atom, with re and si faces. In stereochemistry , prochiral molecules are those that can be converted from achiral to Chirality chemistry chiral in a single step. ref name mcmurry cite book title Organic Chemistry author John E. McMurry John McMurry edition 6ed publisher Brooks Cole pages 301 303 ref ref GoldBookRef title prochirality file P04859 ref If two identical substituent s are attached to a orbital hybridisation sp sup 3 sup hybridized atom , the descriptors pro R and pro S are used to distinguish between the two. Promoting the pro R substituent to higher priority than the identical alternative would result in an R chirality center at the original sp sup 3 sup hybridized atom, and vice versa. A VSEPR trigonal planar sp sup 2 sup hybridized atom can be converted to a chiral center when a substituent is added to the re or si face of the molecule. These faces are labelled re if the substituents at the trigonal atom are disposed in decreasing Cahn Ingold Prelog priority rules Cahn Ingold Prelog priority order in a clockwise order, and si if the priorities decrease in counter clockwise order but the designation of the resulting chiral centre as s or r depends on the priority of the incoming group. References Reflist Category Stereochemistry de Prochiralit t fr Prochiralit gl Proquiralidade it Prochiralit nl Prochiraliteit ja zh ... more details
Image Linear 3D balls.png 200px thumb left Idealised structure of a compound with linear geometry. Image Beryllium fluoride 3D vdW.png 200px thumb right Structure of beryllium fluoride , a compound with a linear geometry. In chemistry , the Linear molecular geometry describes the arrangement of three or more atoms placed at an expected bond angle of 180 . Linear organic molecules, e.g. acetylene, are often described by invoking sp orbital hybridization for the carbon centers. Many linear molecules exist, prominent examples include CO2 CO sub 2 sub , Hydrogen cyanide HCN , and xenon difluoride . Linear anions include azide N sub 3 sub sup nowiki &minus nowiki sup and thiocyanate SCN sup nowiki &minus nowiki sup . Linear cations include Nitronium ion NO sub 2 sub sup sup . ref Greenwood, N. N. & Earnshaw, A. 1997 . Chemistry of the Elements 2nd Edn. , Oxford Butterworth Heinemann. ISBN 0 7506 3365 4. ref See also VSEPR theory AXE method AXE method Molecular geometry References references External links http www.3dchem.com 3D Chem Chemistry, Structures, and 3D Molecules http www.iumsc.indiana.edu IUMSC Indiana University Molecular Structure Center http www.phys.ncl.ac.uk staff njpg symmetry Molecules l3d.html Point Group Symmetry Point Group Symmetry Interactive Examples http chemlab.truman.edu CHEM121Labs MolecularModeling1.htm Molecular Modeling http intro.chem.okstate.edu 1314F97 Chapter9 3BP.html Animated Trigonal Planar Visual MolecularGeometry Category Molecular geometry es Geometr a molecular lineal nl Lineaire moleculaire geometrie ja sv Linj r geometri zh ... more details
Image T shaped 3D balls.png thumb left 200px Idealised structure of a compound with T shaped coordination geometry. Image Chlorine trifluoride 3D vdW.png thumb right 200px Structure of chlorine trifluoride , an example of a compound with T shaped coordination geometry. In chemistry, T shaped molecular geometry describes the structures adopted by some compounds where a central atom has three ligand s. Ordinarily, three coordinated compounds adopt trigonal planar or pyramidal geometries. Example of a T shaped molecules are the halogen trifluorides, such as ClF3 ClF sub 3 sub . ref Greenwood, N. N. & Earnshaw, A. 1997 . Chemistry of the Elements 2nd Edn. , Oxford Butterworth Heinemann. ISBN 0 7506 3365 4. ref According to VSEPR theory T shaped geometry results from three ligands and two lone pairs of electrons bonded to the central atom. The three atoms bond at 90 angles on one side of the central atom, producing the T shape. ref Chemistry Dictionary and Glossary. 2005. http www.ktf split.hr glossary no en o.php?def T shaped 20molecular 20shape ref AXE Type AX sub 3 sub E sub 2 sub . According to Valence Bond Theory, T shaped molecules are assigned sp sup 3 sup d hybridization. It is generally accepted that d orbitals do not contribute to the bonding in such molecules, which can be more simply described using Molecular Orbital Theory . See also AXE method References references External links http www.3dchem.com 3D Chem Chemistry, Structures, and 3D Molecules http www.iumsc.indiana.edu IUMSC Indiana University Molecular Structure Center http www.phys.ncl.ac.uk staff njpg symmetry Molecules l3d.html Point Group Symmetry Point Group Symmetry Interactive Examples http chemlab.truman.edu CHEM121Labs MolecularModeling1.htm Molecular Modeling http intro.chem.okstate.edu 1314F97 Chapter9 3BP.html Animated Trigonal Planar Visual MolecularGeometry Category Molecular geometry es Geometr a molecular en forma de T nl T vormige moleculaire geometrie ja T sv T formad geometri ... more details
Image AX3E0 3D balls.png thumb left 200px Idealized structure of a compound with trigonal planar coordination geometry. Image Boron trifluoride 3D vdW.png thumb right 200px Structure of boron trifluoride , an example of a molecule with trigonal planar geometry. In chemistry , trigonal planar is a molecular geometry model with one atom at the center and three atoms at the corners of a triangle, called peripheral atoms, all in one plane. ref name March Jerry March Advanced Organic Chemistry 3rd Ed. ref In an ideal trigonal planar species, all three ligands are identical and all bond angles are 120 . Such species belong to the point group D sub 3h sub . Molecules where the three ligands are not identical, such as formaldehyde H sub 2 sub CO , deviate from this idealized geometry. Examples of molecule s with trigonal planar geometry include boron trifluoride BF sub 3 sub , formaldehyde H sub 2 sub CO , phosgene COCl sub 2 sub , and sulfur trioxide SO sub 3 sub . Some ions with trigonal planar geometry include nitrate NO sub 3 sub sup sup , carbonate ion CO sub 3 sub sup 2 sup , and guanidine guanidinium C NH sub 2 sub sub 3 sub sup sup . In organic chemistry, planar, three connected carbon centers that are trigonal planar are often described as having orbital hybridisation sp sup 2 sup hybridization . ref Holleman, A. F. Wiberg, E. Inorganic Chemistry Academic Press San Diego, 2001. ISBN 0 12 352651 5. ref ref G. L. Miessler and D. A. Tarr Inorganic Chemistry 3rd Ed, Pearson Prentice Hall publisher, ISBN 0 13 035471 6. ref Nitrogen inversion is the distortion of pyramidal amine s through a transition state that is trigonal planar. Pyramidalization is a distortion of this molecular shape towards a tetrahedral molecular geometry . One way to observe this distortion is in pyramidal alkene s. ref name March See also AXE method Molecular geometry VSEPR theory References references External links http www.3dchem.com 3D Chem Chemistry, Structures, and 3D Molecules http www.ium ... more details
120 . The axial bond angle has changed slightly due to VSEPR Theory VSEPR effects. Because of the increased ... than ideal bond angles are due to VSEPR effects arising from the sterics of the lone pair. Image ... more details
chembox Verifiedfields changed verifiedrevid 476998244 Name Xenon oxytetrafluoride ImageFile Xenon oxytetrafluoride 3D balls.png ImageSize 150px ImageName Ball and stick model of xenon oxytetrafluoride ImageFile1 Xenon oxytetrafluoride 3D vdW.png ImageSize1 150px ImageName1 Space filling model of xenon oxytetrafluoride OtherNames Section1 Chembox Identifiers ChemSpiderID Ref chemspidercite correct chemspider ChemSpiderID 10326200 InChI 1 F4OXe c1 6 2,3,4 5 InChIKey ONRYXFFHIXYZMZ UHFFFAOYAY SMILES F Xe F F F O StdInChI Ref stdinchicite correct chemspider StdInChI 1S F4OXe c1 6 2,3,4 5 StdInChIKey Ref stdinchicite correct chemspider StdInChIKey ONRYXFFHIXYZMZ UHFFFAOYSA N CASNo Ref cascite changed ?? CASNo 13774 85 1 Section2 Chembox Properties Formula XeOF sub 4 sub MolarMass 223.23 g mol Appearance colorless liquid Density 3.17 g cm sup 3 sup , liquid MeltingPt 46.2 C VSEPR square pyramidal Solubility Reacts with water Section3 Chembox Structure CrystalStruct Section7 Chembox Hazards EUClass not listed Xenon oxytetrafluoride Xenon Xe Oxygen O Fluorine F sub 4 sub is an inorganic chemical compound . As are all xenon compounds, it is extremely reactive and unstable, and hydrolyses in water to give dangerously hazardous and corrosive products XeOF sub 4 sub 2H sub 2 sub O Xe 4 hydrogen fluoride HF 3 2 O sub 2 sub In addition, some ozone and fluorine are also formed. The reaction is extremely dangerous, and xenon oxytetrafluoride should therefore be kept away from any trace of water or water vapour under all conditions. References Unreferenced date September 2007 references XeOF sub 4 sub reacts with H sub 2 sub O in the following steps XeOF sub 4 sub H sub 2 sub O XeO sub 2 sub F sub 2 sub 2HF XeO sub 2 sub F sub 2 sub H sub 2 sub O XeO sub 3 sub 2HF Xenon trioxide XeO sub 3 sub is a dangerous explosive, decomposing explosively to Xe and 3 2 O sub 2 sub . External links http webbook.nist.gov cgi cbook.cgi?ID C13774851 WebBook page for XeOF4 Xenon compounds Noble ... more details
chembox verifiedrevid 446441977 Name Chloryl fluoride ImageFile Chloryl fluoride 3D balls.png ImageSize 200px ImageName Chloryl fluoride OtherNames chlorine dioxide fluoride Section1 Chembox Identifiers CASNo Ref cascite correct ?? CASNo 13637 83 7 Section2 Chembox Properties Formula chlorine oxygen 2 fluorine MolarMass 86.4502 g mol Density 3.534 g L MeltingPt 15 C BoilingPt 6 C Chloryl fluoride is the chemical compound with the formula ClO sub 2 sub F. It is commonly encountered side product in reactions of chlorine fluorides with oxygen sources. ref Chrisie, K. O. Wilson, R. D. Schack, C. J. Chloryl fluoride Inorganic Syntheses, 1986, volume 24, pages 3 5. ISBN 0 471 83441 6 ref It is the acyl halide acyl fluoride of chloric acid . Preparation ClO sub 2 sub F was first reported by Schmitz and Schumacheb in 1942, who prepared it by the fluorination of ClO sub 2 sub . ref Schmitz, H. Schumacheb, H. J. ber eine neue Reaktion des Chlordioxyds. Die Bildung einer Verbindung der Formel ClO sub 2 sub F Zeitschrift f r anorganische und allgemeine Chemie 1942, Volume 249, Pages 238 244. DOI 10.1002 zaac.19422490302 ref The compound is more conveniently prepared by treatment of sodium chlorate and chlorine trifluoride and purified by vacuum fractionation, i.e. selectively condensing this species separately from other products. This species is a gas boiling at 6 C 6 NaClO sub 3 sub 4 ClF sub 3 sub &rarr 6 ClO sub 2 sub F 2 Cl sub 2 sub 3 O sub 2 sub 6 NaF Structure In contrast to Dioxygen difluoride O sub 2 sub F sub 2 sub , ClO sub 2 sub F is a pyramidal molecule. This structure is predicted by VSEPR . The differing structures reflects the greater tendency of chlorine to exist in positive oxidation states with oxygen and fluorine ligands. The related Cl O F compound perchloryl fluoride , ClO sub 3 sub F, is tetrahedral. References references External links http webbook.nist.gov cgi cbook.cgi?ID C13637837 WebBook page for ClO2F Chlorine compounds Category Chloryl compounds ... more details
chembox verifiedrevid 366065760 ImageFile Tetramethylammonium pentafluoroxenate xtal 3D vdW.png ImageSize IUPACName Tetramethylammonium pentafluoridoxenonate OtherNames Section1 Chembox Identifiers CASNo PubChem SMILES Section2 Chembox Properties Formula N CH sub 3 sub sub 4 sub XeF sub 5 sub MolarMass 300.4308 g mol Appearance Density MeltingPt BoilingPt Solubility Section3 Chembox Hazards MainHazards FlashPt Autoignition Tetramethylammonium pentafluoroxenate is the chemical compound with the formula N CH sub 3 sub sub 4 sub XeF sub 5 sub . The XeF sub 5 sub sup sup ion it contains was the first example of a planar pentagonal VSEPR theory AX sub 5 sub E sub 2 sub species. ref name Christe cite journal title The pentafluoroxenate IV anion, XeF sub 5 sub sup sup the first example of a pentagonal planar AX sub 5 sub species author Christe K. O., Curtis E. C., Dixon D. A., Mercier H. P.,. Sanders J. C. P, Schrobilgen G. J. journal Journal of the American Chemical Society J. Am. Chem. Soc. year 1991 volume 113 issue 9 pages 3351 3361 doi 10.1021 ja00009a021 ref It was prepared by the reaction of N CH sub 3 sub sub 4 sub F with xenon tetrafluoride , N CH sub 3 sub sub 4 sub F being chosen because it can be prepared in anhydrous form and is readily soluble in organic solvents . ref name Christe The anion is planar, with the fluorine atoms in a slightly distorted pentagonal coordination Xe F bond lengths ranging from 197.9 203.4 pm and Xe F bond angles ranging from 71.5 72.3 . ref name Christe Other salts have been prepared with sodium, caesium and rubidium, and vibrational spectra shows that these contain the same planar ion. ref name Christe File Pentafluoroxenate ion from xtal 3D balls.png 150px Ball and stick model of the pentafluoroxenate ion File Pentafluoroxenate ion 2D.png 150px Structural formula of the pentafluoroxenate ion References reflist Xenon compounds Noble gas compounds Category Fluorides Category Xenon compounds Category Quaternary ammonium compounds fa ... more details
isomers that protein s can take. Types of molecular structure Main article VSEPR Theory AXE method VSEPR theory There are six basic shape types for molecules Linear In a linear model, atoms are connected ... pairs. In accordance with the VSEPR valence shell electron pair repulsion theory , the bond ... the tetrahedral angle to a slightly lower value. An example is NH sub 3 sub ammonia . VSEPR table The bond angles in the table below are ideal angles from the simple VSEPR theory, followed by the actual ... Pair Repulsion theory VSEPR predicts that lone pairs repel each other thus pushing the different atoms away from them. See also VSEPR theory Molecular graphics Molecular modelling Molecular mechanics ... more details
in accordance with valence shell electron repulsion theory VSEPR . Some examples where the lone ... or no distortion, in contravention to valence shell electron repulsion theory VSEPR theory ... more details
, the species adopts a pyramidal structure, in accord with VSEPR theory . Preparation Bismuth ... structure of this coordination complex does not follow the predictions of VSEPR theory ... more details
notability date September 2011 Polysilicon halides are silicon backbone polymer ic solids. At room temperature, the polysilicon fluorides are colorless to yellow solids while the chlorides, bromides, and iodides are, respectively, yellow, amber, and red orange. ref Inorganic Chemistry, Holleman Wiberg, Academic Press 2001 , p. 850. ref Polysilicon dihaildes perhalo Polysilicon hydride polysilenes have the general formula Si X sub 2 sub sub n sub while the polysilicon monohalides perhalo Polysilicon hydride polysilynes have the formula Si X sub n sub , where X is F, Cl, Br, or I and n is the number of monomer units in the polymer. Macromolecular Structure The polysilicon halides can be considered structural derivatives of the Polysilicon hydride Structure polysilicon hydrides , in which the side group hydrogen atoms are substituted with halogen atoms. In the monomeric silicon dihalide aka dihalo silylene and dihalosilene molecule, which is analogous to carbene molecules, the silicon atom is Valence chemistry divalent forms two bonds . By contrast, in both the polysilicon dihalides and the polysilicon monohalides, as well as the polysilicon hydrides, the silicon atom is tetravalent with a local coordination geometry that is VSEPR theory AXE method tetrahedral , even though the stoichiometry of the monohalides Si X sub n sub Si sub n sub X sub n sub might erroneously imply a structural analogy between perhalopolysilynes and linear polyacetylene s with the similar formula C sub 2 sub H sub 2 sub sub n sub . The carbon atoms in the polyacetylene polymer are Orbital hybridisation sp2 hybrids sp sup 2 sup hybridized and thus have a local coordination geometry that is VSEPR theory AXE method trigonal planar . However, this is not observed in the polysilicon halides or hydrides because the Si Si double bond in disilene compounds are much more reactive than C C double bonds. Only when the substituent groups on silicon are very large are disilene compounds kinetically non Labi ... more details
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