The near infrared electronic transition of B3 in a neon matrix

The 1 2 A 2 ″ ← X 2 A 1 ′ electronic transition of the B3 molecule with origin band at 5990 cm−1 has been observed in a 6 K neon matrix. A vibrational progression in the spectrum corresponds to the excitation of the ν1 ( a 1 ′ ) vibrational mode in the 1 2 A 2 ″ state with a frequency of ∼1092 cm−1. The band system was detected after laser ablation of a boron rod and the origin band also after mass-selected deposition of B 3 - anions with subsequent neutralization.