Complex formation of chlorine pentafluoride with Lewis acids and bases

Crystal Structure of ClF4+SbF6-, Normal Coordinate Analyses of ClF4+, BrF4+, IF4+, SF4, SeF4, and TeF4, and Simple Method for Calculating the Effects of Fluorine Bridging on the Structure and Vibrational Spectra of Ions in a Strongly Interacting Ionic Solid

“…Crystal structures, however, are known only for the ClF 2 + salts. − Although these structures confirm the predominantly ionic nature of the adducts, strong interactions between the ClF 2 + cations and the anions were observed which result in infinite chains, distort some of the ions and complicate the vibrational spectra. Chlorine pentafluoride also forms adducts with AsF 5 and SbF 5 , but only the ClF 5 ·SbF 5 complex is stable at room temperature. , On the basis of their vibrational spectra, a predominantly ionic structure was proposed , for the ClF 5 ·MF 5 adducts with ClF 4 + most likely possessing a pseudotrigonal bipyramidal structure of C 2 ν symmetry, similar to those found for isoelectronic SF 4 and the heavier halogen analogues BrF 4 + and IF 4 + . , In view of the significant cation−anion interactions found for the related ClF 2 + salts, − it was desirable to confirm by X-ray diffraction the postulated C 2 ν structure for ClF 4 + , to obtain its exact geometry, and to determine the nature and influence of any interionic interactions. Electronic structure calculations were used to critically examine the previously reported crystal structures for BrF 4 + 25 and IF 4 + , , and the vibrational spectra of theClF 4 + , BrF 4 + , and IF 4 + cations , and of the isoelectronic SF 4 , SeF 4 , and TeF 4 molecules.…”

Crystal Structure of CIF4+SbF6-, Normal Coordinate Analyses of CIF4+ BrF4+, IF4+, SF4, SeF4, and TeF4, and Simple Method for Calculating the Effects of Fluorine Bridging on the Structure and Vibrational Spectra of Ions in a Strongly Interacting Ionic Solid

“…Chlorine pentafluoride also forms adducts with AsF 5 and SbF 5 , but only the ClF 5 -SbF 5 complex is stable at room temperature. 21 ' 22 Based on their vibrational spectra, a predominantly ionic structure was proposed 22 ' 23 for the C1F 5 -MF 5 adducts with C1F 4 + most likely possessing a pseudo-trigonal bipyramidal structure of C2 V symmetry, similar to those found for isoelectronic SF4 and the heavier halogen analogues BrF 4 + 25 and IF 4 + . 26 ' 27 In view of the significant cation-anion interactions found for the related C1F 2 + salts, 15 " 20 it was desirable to confirm by x-ray diffraction the postulated C 2v structure for C1F 4 + , to obtain its exact geometry, and to determine the nature and influence of any interionic interactions.…”

“…A sample of ClF 4 + SbF6~ was prepared as previously described, 21,22 and single crystals were grown from solutions in anhydrous HF. Due to the moisture sensitivity of the crystals, a suitable crystal was selected and mounted with a drop of perfluoroether oil under a flow of cold dry nitrogen.…”

Heterocations in Superacid Systems

“…(4.206)]. There is no certain evidence for the I 2 Cl þ cation 335, but presumably the electrical conductivity of liquid ICl (specific conductance ¼ 4.60 10 À3 ohm À1 cm À1 at 35 C) which has previously been ascribed to the self-ionization 829 830 The 19 F NMR spectrum of ClF 4 þ (a doublet with equal intensity) suggests two pairs of nonequivalent fluorine ligands and a structure of C 2v symmetry. ICl 2 þ Ion.…”