On the accuracy of ab initio methods in predicting the electric dipole moment function of carbon monoxide

Accurate electric dipole moment function of the CO molecule in its ground electronic state $X{}^1{\Sigma }^{+}$ has been determined using the single-reference coupled-cluster approach, up to the CCSDTQP level of approximation, in conjunction with the augmented core-valence correlation-consistent basis sets, aug-cc-pCV$n$Z, up to octuple-zeta quality. The ab initio predicted function is compared with its experimentally-derived counterparts. The accuracy of applied theoretical methods is discussed.