Ab initio electro-optical properties crucial to the parity-changing vibrational Raman scattering by gaseous carbon dioxide

By applying various schemes of the DALTON program suite, the derivatives of the dipole-quadrupole $(\hat A)$ and dipole-magnetic dipole $(\hat G)$ polarizabilities by the asymmetric stretching coordinate of CO$_2$ are derived. The $\hat G$ derivative was calculated for the first time whereas the obtained cartesian components of $\hat A$ favourably agree with the available up-to-date values. Based on the thus derived electro-optical parameters, we provide estimations of the intensity of the forbidden vibrational $\nu_3$ Raman transition in CO$_2$ which show the leading role of the magnetic eects. The results might be guiding to detect and to quantitatively interpret this novel, vibrational parity-changing Raman process.