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THz and Submillimeter-wave Spectroscopy of Molecular Complexes

  1. Keiichi Tanaka1,
  2. Kensuke Harada1,
  3. Koichi M.T. Yamada2

Published Online: 15 SEP 2011

DOI: 10.1002/9780470749593.hrs029

Handbook of High-resolution Spectroscopy

Handbook of High-resolution Spectroscopy

How to Cite

Tanaka, K., Harada, K. and Yamada, K. M. 2011. THz and Submillimeter-wave Spectroscopy of Molecular Complexes. Handbook of High-resolution Spectroscopy. .

Author Information

  1. 1

    Kyushu University, Department of Chemistry, Fukuoka, Japan

  2. 2

    National Institute of Advanced Industrial Science and Technology, Tsukuba, Japan

Publication History

  1. Published Online: 15 SEP 2011


This article reviews the recent progress of terahertz (THz) and submillimter-wave (SMMW) spectroscopy in the frequency range of 10–300 cm−1 and its application to the study of weakly bound molecular complexes.

The first section describes the light sources used for generating THz radiation, which includes the backward-wave oscillators (BWO), the multipliers with the GaAs monolithic membrane diode (MOMED), and the supperlattice electronic devices (SLED), as well as the tunable far infrared (TuFIR) lasers.

In the following section, we introduce extremely sensitive spectrometers developed for observing very weakly bound molecular complexes, such as the intra-cavity OROTRON spectrometer and the millimeterwave-Fourier transform microwave (MMW-FTMW) double resonance spectrometer. We also review the traditional millimeter-wave spectrometers, electric-resonance optothermal spectrometers (EROS), and the tunable far-infrared (TuFIR) laser spectrometers, which have also been applied successfully to study weakly bound molecular complexes.

In the last section, the recent topics of the THz and millimeterwave spectroscopy of molecular complexes are reviewed in the four subsections; (i) Rare gas-molecule complexes: Rg-HX, Rg-CO, and Rg-HCN, (ii) dimers: (CO)2, CO-N2, HCN-H2, and (H2O)2, (iii) water complexes (H2O)n, with n up to 6, and (iv) ion and radical complexes: Ar[BOND]SH, Ar[BOND]H2O, H2O[BOND]HO2, and Ar[BOND]H3+.


  • THz spectroscopy;
  • submillimeter-wave spectroscopy;
  • molecular complexes;
  • large amplitude internal motion;
  • intermolecular forces;
  • intermolecular potential energy surface