VIBRATIONAL INFRARED-SPECTRUM OF THE GROUP-IV TRANSITION-METAL NITRIDE GASEOUS MOLECULES

The infrared spectrum of TiN, ZrN, and HfN has been observed in absorption by using a microwave discharge through MCI4/N2 mixtures as the molecular source. The molecular constants determined for each molecule are as follows: TiN ZrN HfN v0(cm-1) 969.6(20) 936.6(20) 919.5(20) Be(cm-1) 0.623(6) 0.483(4) 0.457(9) αe XlO3 (cm-1) 4.08(4) 3.01(3) 1.02(6) re(nm) 0.158(1) 0.170(1) 0.169(3) The agreement between the values of the rotational constants reported previously for TiN and ZrN establishes that each molecule has a 2σ ground state. The appearance of the infrared spectrum indicates that HfN also has a 2Σ ground state. © 1979 American Institute of Physics.