The vibrational parity of a centrosymmetric molecule can be broken in the Raman
spectra when the electric-dipole (E1) virtual transitions are accompanied by the
electric-quadrupole (E2) or magnetic-dipole (M1) ones. To assess the intensity of
the not yet detected ν2 CO2 Raman band, accurate ab initio values of the mixed
E1-E2 (Aˆ) and E1-M1 (Gˆ) polarizabilities of a bent CO2 are presently obtained
using the DALTON program suite. The previous SCF results of Amos, Buckingham and Williams (Mol. Phys. 39, 819 (1980)) for the Aˆ-tensor components are
substantially refined by employing the extended basis sets and accounting for the
electron correlation (up to CCSD). By using the SOPPA approach, the derivatives
of Gˆ are obtained for the first time. The results are processed to derive the rank-r
irreducible spherical tensors (IST) Xκ(r) which vary in space as the Wigner functions Dκm (r) whose subscript κ determines the dependence on the bent-molecule plane
orientation relative to the symmetry axis. As a result, four ISTs (A(1) 1 , A(2) 1 , A(3) 1
and A(3)
3 ) fully determine the ν2 E1-E2 intensity whereas two tensors G(1) 1 and G(2) 1
do the same for the magnetic channel. Using the thus derived properties, the integrated ν2−band intensities are calculated for the first time and, like our recent
assessments for the ν3 band (Opt. Spektrosk. 133, 607 (2025)), show the leading
role of the E1-M1 terms. The results could be helpful for detection of this novel
parity-changing Raman process.