Calculation of polarizabilities of low-lying states of Ag

The transition-metal silver atom has recently begun to attract increased attention from theo-

rists and experimentalists. For example, atomic silver can be used in optical lattice clocks using

the electric quadrupole 4d¹⁰5s ²S_1/2 − 4d⁹5s^{2 2}D_5/2 transition as a clock transition. One of the

other interesting features of silver is its ability to form ultracold, highly polar diatomic molecules

containing the silver atom (in its ground state) interacting with a noble gas, an alkali-metal or an

alkaline-earth-metal atom.

To support the experimental efforts, we calculated the dc and ac polarizabilities (at the wave-

lengths 532 nm and 1064 nm convenient for laser trapping) for the lowest-lying even and odd-parity

states of Ag. A specific feature of the Ag atom is that along with the states belonging to the con-

figuration 4d¹⁰x (where x ≡ 5, 6s; 5, 6p, 5d, etc.), there are also low-lying states with the unfilled 4d

shell 4d⁹5s^{2 2}D_3/2,5/2.

To calculate the properties of the 4d¹⁰x states, we used a single-electron method, such as many-

body perturbation theory (MBPT) over the residual Coulomb interaction, or using an all-order,

linearized coupled-cluster single-double (LCCSD) method. For calculating the properties of the

4d⁹5s^{2 2}D_3/2,5/2 states, a single electron approach is not applicable. In this case, we consider Ag as

an atom with many valence electrons and apply the 11- and 17-electron configuration intaction (CI) method.