The transition probabilities and relative band intensities for the ultraviolet (

{}^{2}Σ_{u}^{+} \to {}^{2}Σ_{g}^{+}

) and infrared (

{}^{2}Σ_{u}^{+} \to {}^{2}Π_{g}

) absorption bands of the

V_{K}

center have been calculated using an approximate valence-bond wave function for the halogen-molecule anion. The most significant feature of this wave function is that it permits an approximate treatment of correlation between electrons of opposite spin. Intra-atomic electron correlation is included by using ionic orbitals for

A

and neutral-atom orbitals for

B

in valence-bond structures of the form

X_{A}^{-} \dots X_{B}

and vice versa in structures of the form

X_{A} \dots X_{B}^{-}

. Interatomic electron correlation is treated by a perturbation-theory calculation of the polarization of

X_{A}

by the negative charge on

X_{B}^{-}

in the

X_{A} \dots X_{B}^{-}

structures and vice versa in the

X_{A}^{-} \dots X_{B}

structures. It is found that the correction for intra-atomic electron correlation yields considerably improved agreement between the calculated and observed intensities of the

π

-polarized part of the infrared transition. Calculations of the other transition intensities, such as the uv transition, and the

σ

-polarized part of the infrared transition which is "stolen" from the uv transition by spin-orbit mixing of

σ

and

π

states, are unaffected by the correction for electron correlation. It is also found, however, that interatomic electron correlation makes a major contribution to the isotropic hyperfine interaction in these molecules.

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