Soft Bending Modes of Terminal Chlorides in Gaseous Two- and Three-Coordinate Cu(II)−Cl Species

Abstract

The structures and vibrational spectra of the monomer and dimer of copper dichloride as well as the 1:1 complexes with aluminum and gallium trichloride, CuAlCl5 and CuGaCl5, have been studied using ab initio and density functional methods. For all molecules, equilibrium structures corresponding to minima on the potential energy surface were found to possess the ideal and expected D ∞ h , D 2 h , or C 2 v symmetries, respectively. These complexes are, however, easily distorted through bending of the terminal chlorines connected to copper in the plane of the singly occupied orbital in Cu d9. Calculated bending potentials show that the corresponding modes are very soft. For the higher associates of CuCl2, vibrational bands that may facilitate the verification of the structures are presented.

How Inert, Perturbing, or Interacting Are Cryogenic Matrices? A Combined Spectroscopic (Infrared, Electronic, and X-ray Absorption) and DFT Investigation of Matrix-Isolated Iron, Cobalt, Nickel, and Zinc Dibromides

“…For example, the different populations of the metal-based σ g , π g , and δ g orbitals (Table ) and the presence of low-lying linear and bent excited states are intrinsic properties of the metal dihalides that affect the way they can interact with the matrix host as well as the relative ease with which the dihalides can bend. The soft-bending modes in CuCl 2 have been studied previously . Hastie et al , estimated the frequencies of ν 2 for CoF 2 (151 cm –1 ), NiF 2 (142 cm –1 ), and ZnF 2 (157 cm –1 ) using gas-phase data with an uncertainty of ±30 cm –1 .…”

“…The soft-bending modes in CuCl 2 have been studied previously. 212 Hastie et al 139,185 estimated the frequencies of ν 2 for CoF 2 (151 cm −1 ), NiF 2 (142 cm −1 ), and ZnF 2 (157 cm −1 ) using gas-phase data with an uncertainty of ±30 cm −1 . Thompson and Carlson 99 observed ν 2 for MnCl 2 (83 cm −1 ), FeCl 2 (88 cm −1 ), CoCl 2 (94.5 cm −1 ), NiCl 2 (85 cm −1 ), and NiBr 2 (69 cm −1 ).…”

Three-Coordinate [CuIIX3]− (X=Cl, Br), Trapped in a Molecular Crystal

“…[13] Our procedure for evaluation and validation of functionals (BLYP, VWN) for the present purposes involved calculation of the geometry and vibrational frequencies of CuCl 2 , [14] and the geometries of [Cu 2 Cl 6 ] 2À and [Cu 2 Br 6 ] 2À . Details are given in the Supporting Information.…”

“…Unrestricted density functional calculations were performed with numerical basis sets as implemented in the program DMol. [13] Our procedure for evaluation and validation of functionals (BLYP, VWN) for the present purposes involved calculation of the geometry and vibrational frequencies of CuCl 2 , [14] and the geometries of [ [15] we showed that the VWN functional slightly overestimates intermolecular energies, and that VWN-calculated intermolecular energies scaled by 0.7 yield experimental energies for arene ¥¥¥ arene in- Figure 1. The molecular structures of the anions in 1 ± 5, with atom labels for the asymmetric unit (4 is centrosymmetric and the centroid of 5 is at a 222 (D 2 ) site), and thermal ellipsoids at 50 % probability.…”

Fourier Transform Spectra of the E2Πu–X2Πg(3/2) System of CuCl2

“…(15), Ϫ0.429, is due to the mistake, mentioned above, in the earlier calculation of the second-order diagonal Renner-Teller term. In the present paper, we have corrected this contribution and have also added the third-order term, which appear in the H(1, 3) and H(2, 4) terms of matrix for v 2 ϭ 2 levels, (21). The data could however be fitted equally well with the opposite sign.…”