Radiative transition probabilities and lifetimes for the band systems (1) <f>3Π–X 3Σ-</f> and (2) <f>3Σ-–X 3Σ-</f> of the isovalent molecules BeC, MgC, and CaC

Accurate potential energy curves, transition moments, spectroscopic constants, radiative transition probabilities, and lifetimes for the states <f>X 3Σ-</f>, (1) <f>3Π</f>, and (2) <f>3Σ-</f> of BeC, MgC, and CaC are reported using high level calculations. Diagonal transitions dominate for the (2) <f>3Σ- → X 3Σ-</f> system, with band origins falling at 745, 648, and 770 nm, and an intensity ratio of 6,3,1, respectively for BeC, MgC, and CaC. Radiative lifetimes for <f>v′=0</f> are equal to 0.48, 1.45, and 3.29 μs for the state (2) <f>3Σ-</f>, and equal to 13.57, 10.44, and 9.62 μs for the state (1) <f>3Π</f> for BeC, MgC, and CaC. [Copyright &y& Elsevier]