Ab initio study of radium monofluoride (RaF) as a candidate to search for parity- and time-and-parity–violation effects

Relativistic ab initio calculations have been performed to assess the suitability of RaF for experimental search of $P$- and $T$-and-$P$–violating interactions. The parameters of $P$- and $T,P$-odd terms of the spin-rotational Hamiltonian have been calculated for the ${}^2\Sigma$ electronic ground state of the ${}^{223}\mathrm{RaF}$ molecule. They include the $W_a$ parameter, which is critical in the experimental search for nuclear anapole moment, and the parameters $W_d$ and $W_{\mathrm{SP}}$ required to obtain restrictions on the electric dipole moment of the electron and $T,P$-odd scalar-pseudoscalar interactions, respectively. The parameter $X$ corresponding to the “volume effect” in the $T,P$-odd interaction of the ${}^{223}\mathrm{Ra}$ nuclear Schiff moment with electronic shells of RaF has also been computed. Spectroscopic and hyperfine structure constants for ${}^{223}\mathrm{RaF}$ and ${}^{223}{\mathrm{Ra}}^{+}$ have been computed as well, demonstrating the accuracy of the methods employed.