Collection of Czechoslovak Chemical Communications - digital archive 

Abstract

Using semiempirical CNDO-UHF method the adiabatic potential surface of ²[Cu(OH)₆]^4- complexes is investigated. The values of vibration and vibronic constants for E_g - (a_1g + e_g) vibronic interaction attain extremal values for the optimal O-H distance. The Jahn-Teller distortion decreases with increasing O-H distance. The discrepancy between experimentally observed elongated bipyramid of [Cu(OH)₆]^4- in Ba₂[Cu(OH)₆] and the compressed one obtained by quantum-chemical calculation is explainable by hydrogen bonding of the axial hydroxyl group.