Theoretical study of Pu and Am tetracarbide molecules

The electronic structure and ground-state molecular properties of Pu and Am tetracarbides have been investigated by relativistic multireference calculations using CASSCF/CASPT2 theory as well as by density functional theory using the B3LYP exchange-correlation functional in conjunction with relativistic pseudopotentials. The CASSCF/CASPT2 treatment has been extended by spin-orbit coupling effects for selected species using the complete active space state interaction (CASSI) method. The five atoms can form various structural isomers, from which twelve ones have been located in our study. The electronic ground state in both molecules corresponds to a planar fan-type structure of C2v symmetry, in which the actinide atom is connected to a bent C4 moiety. The other structures are much higher in energy, the ones computed in the present study appear between 250-1050 kJ/mol. The bonding characteristics in the most relevant structures have been analysed on the basis of the valence molecular orbitals and Natural Bond Orbital Analysis. The most stable structures have been characterised by their spectroscopic properties; the IR and Raman spectra have been predicted by B3LYP, while the electronic spectra by CASSI calculations.

POGANY Peter;  KOVACS Attila;  KONINGS Rudy; 

2014-06-13

WILEY-BLACKWELL

JRC86568

0020-7608,   

http://onlinelibrary.wiley.com/doi/10.1002/qua.24628/abstract,    jsessionid=D0B358E1E96CF226CB26FB50768D6499.f01t03,    https://publications.jrc.ec.europa.eu/repository/handle/JRC86568,   

10.1002/qua.24628,