Infrared spectra of matrix-isolated uranium oxide species. I. The stretching region

Abstract

Stretching modes of several uranium oxide species vaporized from tungsten and iridium Knudsen cells and deposited in argon and krypton matrices have been observed in the 700–-900 cm−1 region of the infrared. Studies of the spectra as a function of temperature and composition of the condensed urania together with normal coordinate analyses of the spectra of 16O and 18O-containing species have led to the following assignments for the 16O species in argon: U16O(ν) = 820.0 cm−1; U16O2(ν3) = 776.1 cm−1, U16O2(ν1) = 765.4 cm−1 (calc). The spectroscopic evidence strongly indicates a linear geometry for UO2. Tentative assignments for the stretching modes of UO3 are also given.

Infrared Absorption Study of Uranium Trioxide Phases

“…The shortest U-O bond distance was found to be 1.796 Â. WAIT [11][12][13][14] 750cm" 1 Fund., F\ u , U-0 stretch. [8].…”

“…The infrared spectra of U0 3 phases have been studied by several investigators [2][3][4][5][6][7][8][9][10][11][12][13][14][15], Although the spectra were similar, these workers differed in their interpretation and assignment of the observed bands. In particular HOEKSTRA and SIEGEL [2] observed two absorption bands in the uranyl region which are indicative of symmetric (i^s = 860 cm" 1 ) and asymmetric (v" = 930 cm" 1 ) vibrations.…”

A matrix isolation FTIR investigation of laser-ablated uranium oxide in argon and nitrogen matrices

“…The relatively weaker features at 746 and 852 cm-1 are due to the v2 and v4 vibrations of UO3. These assignments are based on the earlier K-cell matrix isolation work, where the vapour phase species over uranium oxide at a maximum temperature of 1900 K, were trapped in an argon matrix (Gabelnick et al 1973b). The laser ablation process in which the temperatures at the sample were in excess of 2500 K has therefore yielded principally the same vapour phase species as the K-cell work.…”

Strong electron correlation in UO2−: A photoelectron spectroscopy and relativistic quantum chemistry study

“…The UO 2 molecule has been an important model system for actinide chemistry and has been extensively studied both experimentally and theoretically. [2][3][4][5][6][7][8][9][10][11][12][13][14][15][16] UO 2 is known to be a linear molecule with a 3 2u ground state and a (7sσ g ) 1 (5fφ u ) 1 a) W. L. Li and J. Su contributed equally to this work. b) Electronic mail: junli@tsinghua.edu.cn.…”