The Nature of Bonding in IrC

摘要

The nature of bonding in the title compound has been stUdied by using CASSCF andFOCI techniques. The ground state of IrC has been found to be 2△ arising primarilyfrom:.. 1σ2 2σ2 1π4 1δ3 3σ2 configuration, which forms a triple bond between Ir and C atoms (one σ;two π). The lowest quartet state is 4Φ state which has the configuration:... 1σ2 2σ2 1π4 1δ3 2π1 3σ2 andlies higher than the ground state by 1 .25eV. The molecular constants of the ground state calculatedat CASSCF level by using Morse’s mode are: Re=1.6904A, De=4.86eV, We=1139cm-1, andB0=0.5219cm-1 comparable with the spectrum values (Re=1 .6858A, De=6.44 eV, We=1051cm-1and B0=0.5251 cm-1).