ISSN:
1089-7690
Source:
AIP Digital Archive
Topics:
Physics
,
Chemistry and Pharmacology
Notes:
New fundamental K–O stretching frequencies of the isolated potassium peroxide K2O2 molecule are reported for different isotopic species. The B2u vibration can be measured for 39K216O2, 39K216O18O, K217O18O, 39K218O2, 39K41K16O2 and 39K41K18O2. The B3u vibration can be located for K216O2, K216O18O and K218O2 products, and the formerly B3g symmetry motion, IR-activated by symmetry breaking in 39K216O18O, 39K41K16O18O, 39K41K16O2, and 39K41K18O2, is equally observed. The self-consistency of the attributions is based on semiempirical quadratic force field calculations, and, more importantly, upon theoretical ab initio and Density Functional Theory calculations. The ground state geometry calculated using the all electron density functional theory method corresponds to a slightly out of plane distorted rhombic structure (C2v symmetry), in contrast to the D2h symmetry structure calculated for Li2O2 or at the SCF level for K2O2. The energy difference between rhombic D2h and out-of-plane C2v structure is nevertheless too small (0.08 kcal/mol) to exclude a calculation artefact. The agreement between the positions of observed vibrations and the density functional theory calculation predictions is however remarkable. © 1995 American Institute of Physics.
Type of Medium:
Electronic Resource
URL:
http://dx.doi.org/10.1063/1.469804
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