L. Andrews et al., Reactions of laser-ablated U and Th with CO2: Neon matrix infrared spectraand density functional calculations of OUCO, OThCO, and other products, J AM CHEM S, 122(46), 2000, pp. 11440-11449
Laser-ablated U and Th atoms react with CO2 to give OUCO (1806.9, 823.2 cm(
-1)) and OThCO (1778.4 cm(-1)) as major products, which are identified by i
sotopic substitution ((CO2)-C-13, (CO2)-O-18 and (CO2)-C-12 + (CO2)-C-13, (
COO)-O-16-O-18 + (CO2)-O-18 mixtures), doping with CCl4 as an electron trap
, and comparison with frequencies from density functional calculations. The
insertion reaction is spontaneous as these bands increase on annealing the
neon matrix from 4 to 6 K. Further reaction of OAnCO (An = Th, U) with ano
ther CO2 molecule gives the O(2)An(CO)(2) product, although much more so wi
th uranium than thorium. Reaction of the metal cations with CO2 produces OU
CO+ (2073.0, 881.2 cm(-1)) and OThCO+ (2009.9, 896.4 cm(-1)) with higher yi
eld in thorium experiments. The O(2)An(CO)(2)(-) anions are observed for bo
th metals again with higher yield in uranium investigations.