Syntheses and Structural Characterizations of the Cl(V) Coordination Complex, [O2Cl(FXeF)2][AsF6], and β-[ClO2][AsF6]

XeF2 Coordination Complexes of the [BrO2]+ Cation, [O2Br(FXeF)n][AsF6] (n = 1, 2) and [O2Br(FXeF)2][SbF6]; Their Syntheses and Structural Characterizations

“…Attempts to optimize various oligomeric models failed at the B3LYP/ Def2-TZVPD, APFD/Def2-TZVPD, and PBE1PBE/Def2-TZVPD levels of theory. This contrasts with [O 2 Cl(FXeF) 2 ]-[AsF 6 ], 28 whose discrete structural unit is well reproduced by gas-phase quantum-chemical (QC) calculations that provided calculated frequencies and vibrational mode displacements that facilitated its solid-state vibrational assignments. The calculated optimized gas-phase geometry of [BrO 2 ] + and associated The Raman spectrum was recorded for a dry crystalline mixture of 1, [BrO 2 ][AsF 6 ], and XeF 2 in an FEP sample tube at −150 °C using 1064-nm excitation, where 1 was the dominant species (see Figure 4).…”

“…28 In a prior study, a cationic Br(V) coordination complex of [BrO 2 ] + with BrO 2 F, [O 2 Br(BrO 2 F) 2 ][AsF 6 ], 29 analogy with [ClO 2 ] + . 28 Coordination of NgF 2 to a high-valent Lewis acid cation center is challenging because the cation must not be Lewis acidic to the extent that fluoride-ion abstraction occurs to form a [NgF] + salt. The present study demonstrates that [BrO 2 ] + meets this criterion and provides the first examples of structurally characterized coordination complexes of the [BrO 2 ] + cation with a noble-gas fluoride, XeF 2 .…”

“…26−28 Such intermolecular couplings also occur between the symmetrically bridged XeF 2 ligands of 1 and 2 (F 3 , F 3A and F 4 , F 4A ) and between the two asymmetrically bridged XeF 2 ligands of 3 (F 1 , F 2 and F 3 , F 4 ), and have been assigned accordingly. Vibrational band assignments for [PnF 6 ] − (Pn = As, Sb) were aided by comparisons with those of other [PnF 6 ] − salts 21,28,30,31 and are listed under assumed O h symmetry, although symmetry lowering of the [PnF 6 ] − anions from their gas-phase O h symmetries to lower local symmetries occurs in their structural units. Initial factor-group analyses using the "correlation method" 36 showed that correlation of the gas-phase symmetries of the structural units (C 1 ) to the crystallographic site symmetries of isotypic 1 and 2 (C 1 , Z = 2) and, in turn, to their unit cell symmetries (P1̅ ≡ C i ) predicts that vibrational coupling between the two equivalent structural units of 1 and 2 occurs to give a maximum of 3n − 6 Raman-active A g and 3n − 6 infrared-active A u bands.…”

“…and out-of-phase (o.o.p.) couple to give four modes, [ν(Xe 1 -F 1 ) 28 The highest frequency bands (545.9 cm −1 , i.p. ; 525.6 cm −1 , o.o.p.)…”

“…The Lewis acidity of the [BrOF 2 ] + cation was previously exploited to form coordination complexes with NgF 2 (Ng = Kr, Xe). The reactions of [BrOF 2 ][AsF 6 ] with oxidatively resistant NgF 2 ligands in anhydrous HF (aHF) solvent yielded [F 2 OBr(FNgF) 2 ][AsF 6 ] (Ng = Kr, Xe) and [F 2 OBr(FXeF)][AsF 6 ] (eqs and ), which were structurally characterized by low-temperature (LT) Raman spectroscopy and LT single-crystal X-ray diffraction (SCXRD). [ BrOF 2 ] [ AsF 6 ] + XeF 2 → RT aHF [ F 2 OBr false( FXeF false) ] [ AsF 6 ] [ BrOF 2 ] [ AsF 6 ] + 2NgF 2 → RT aHF [ F 2 OBr ( FNgF ) 2 ] [ AsF 6 ] Most recently, the reaction of [ClO 2 ][AsF 6 ] with XeF 2 provided the first example of a cationic Cl(V) coordination complex with a noble-gas fluoride, [O 2 Cl(FXeF) 2 ][AsF 6 ], which was structurally characterized by LT Raman spectroscopy and LT SCXRD . These studies showed that NgF 2 coordinates to the Lewis acidic [ClO 2 ] + and [BrOF 2 ] + cations through primarily electrostatic Cl---F Xe and Br---F Ng bonds that are directed toward regions of high electrostatic potential on the...…”