Vibrational satellite of Na(3d ← 3s) dipole-forbidden transition in Na/CF4 mixture

Excitation spectra of Na fluorescence in mixtures with CF4 display a new band shifted by the energy of one-vibrational quantum of the IR active ν3-mode of CF4 (1281 cm−1) from Na 3d states. This band is attributed to a Na(3s)⋯CF4(ν3 = 0) → Na(3d)⋯CF4(ν3 = 1) transition and its intensity is explained by coupling with Na(4p)⋯CF4(v3 = 0) resonance state which lies ∼ 180 cm−1 below in energy. An analogous satellite of the Na 6p state combined with the same vibration and lying close to the Na 7p state is reported and discussed.