The first three electronically excited states in the alkaline-earth-metal atoms magnesium, calcium, and strontium comprise the $\left(nsnp\right){}^{3}P_J^o\left(J=0,1,2\right)$ fine-structure manifold. All three states are metastable and are of interest for optical atomic clocks as well as for cold-collision physics. An efficient technique—based on a physically motivated potential that models the presence of the ionic core—is employed to solve the Schrödinger equation for the two-electron valence shell. In this way, radiative lifetimes, laser-induced clock shifts, and long-range interaction parameters are calculated for metastable Mg, Ca, and Sr.

• Received 24 November 2003

DOI:https://doi.org/10.1103/PhysRevA.69.042510