Infrared spectra and tunneling dynamics of the N2-D2O and OC-D2O complexes in the v2 bend region of D2O

• Published in: The Journal of chemical physics 2013-12, Vol.139 (21), p.214309-214309
• Main Authors: Zhu, Yu, Zheng, Rui, Li, Song, Yang, Yu, Duan, Chuanxi
• Format: Article
• Language: English
• Subjects: Bending vibration; Constants; Dependence; Excitation; Heavy water; Infrared spectra; Physics; Tunable lasers; Vibrational states
• ISSN: 0021-9606; 1089-7690
• DOI: 10.1063/1.4836616

The rovibrational spectra of the N2-D2O and OC-D2O complexes in the v2 bend region of D2O have been measured in a supersonic slit jet expansion using a rapid-scan tunable diode laser spectrometer. Both a-type and b-type transitions were observed for these two complexes. All transitions are doubled, due to the heavy water tunneling within the complexes. Assuming the tunneling splittings are the same in K(a) = 0 and K(a) = 1, the band origins, all three rotational and several distortion constants of each tunneling state were determined for N2-D2O in the ground and excited vibrational states, and for OC-D2O in the excited vibrational state, respectively. The averaged band origin of OC-D2O is blueshifted by 2.241 cm(-1) from that of the v2 band of the D2O monomer, compared with 1.247 cm(-1) for N2-D2O. The tunneling splitting of N2-D2O in the ground state is 0.16359(28) cm(-1), which is about five times that of OC-D2O. The tunneling splittings decrease by about 26% for N2-D2O and 23% for OC-D2O, respectively, upon excitation of the D2O bending vibration, indicating an increase of the tunneling barrier in the excited vibrational state. The tunneling splittings are found to have a strong dependence on intramolecular vibrational excitation as well as a weak dependence on quantum number K(a).