Structure and stability of xenon insertion compounds of hypohalous acids, HXeOX [X=F, Cl, and Br]: An ab initio investigation

Abstract

The structure and stability of xenon-inserted hypohalous acids HXeOX (X=F, Cl, and Br) have been investigated theoretically using ab initio molecular orbital calculations. All these molecules are found to consist of a nearly linear HXeO moiety and a bend XeOX fragment. Geometrical parameters of HXeOX are comparable with that of experimentally observed HXeOH species. The dissociation energies corresponding to the lowest-energy fragmentation products, HOX+Xe have been computed to be -398.1, -385.5, and -386.7 kJmol for HXeOF, HXeOCl, and HXeOBr, respectively, at the MP2 level of theory. The respective barrier heights corresponding to the bent transition states (H-Xe-O bending mode) have been calculated to be 138.1, 138.4, and 138.2 kJmol with respect to HXeOX minimum. These species are found to be metastable in their respective potential-energy surface, and the dissociation energies corresponding to the H+Xe+OX products are found to be 56.8, 66.0, and 80.8 kJmol for HXeOF, HXeOCl, and HXeOBr, respectively. The energies corresponding to the H+Xe+O+X dissociation channel have been computed to be 272.0, 309.3, and 299.7 kJmol for HXeOF, HXeOCl, and HXeOBr, respectively, at the same level of theory. Energetics as well as geometrical considerations suggests that it may be possible to prepare these species experimentally similar to that of HXeOH species at low-temperature laser photolysis experiments.

Prediction of a Neutral Noble Gas Compound in the Triplet State

“…For instance, of late, the HXeOBr molecule has been prepareda nd characterized experimentally by Khriachtchev et al, [25] which was theoretically predicted earlier by our group. [22] Generally,t he insertion-type noble gas compounds have ac ommonf ormula, XNgY,i nw hich Xi sh ydrogen or halogen or pseudo-halogen, Ng is an oble gas atom, and Yi sa ne lectronegative atom or group. These XNgY molecules are truly chemically bound species and are generally associated with ac losed-shell electronic configuration.…”

Theoretical investigation of rare gas hydride cations: HRgN2+ (Rg=He, Ar, Kr, and Xe)

“…ement or group) revolutionized the chemistry of rare gas atoms. [31][32][33][34][35][36][37][38][39][40][41][42][43][44] In these systems the Rg atoms are inserted between the atoms of regular stable molecules and the structures are optimized using quantum computational methods. The stability of the predicted molecular species is usually determined by computing the energy diagram of the various possible unimolecular dissociation channels.…”

“…For example, very recently HXeOBr molecules have been prepared and characterized experimentally by Khriachtchev et al, 45 which was theoretically predicted by us earlier. 39 However, cationic rare gas containing species of the type HRgX + are limited and little explored except the recently predicted HRgCO + (Ref. 46 50) have also been predicted theoretically.…”

Structure and stability of noble gas bound compounds (E = C, Ge, Sn, Pb; X = H, F, Cl, Br)

“…The development of noble gas chemistry is now in full swing as authenticated by the speed at which several noble gas (Ng) compounds are being reported by experimentalists and theoreticians . If we look at the Ng compounds having group 14 elements, several of them with NgC bonds can be found, which were experimentally detected in a cryogenic condition by matrix‐isolation technique.…”