Yasuki Endo

Fourier-transform microwave spectroscopy of the HCCN radical. Determination of the hyperfine coupling constants

Two low‐J transitions, N(J)=1(0)−0(1) and 1(2)−0(1), of the HCCN radical in its 3Σ− ground state have been studied by a pulsed‐discharge‐nozzle Fourier‐transform microwave spectrometer. Spectrum with well‐resolved hyperfine splittings due to hydrogen and nitrogen nuclei was observed, which enabled us to determine accurate hyperfine coupling constants for both the nuclei for the first time in the present study, as well as a much improved spin–spin coupling constant. These hyperfine coupling constants suggest that the electronic structure of the HCCN radical can be described as the one with the allenic structure to be almost twice more important than the carbenic structure. The present results seems to support a conclusion that the molecular structure of the radical is almost linear with a possibility of a large amplitude bending motion.

A SEARCH FOR THE HOCO RADICAL IN THE MASSIVE STAR-FORMING REGION Sgr B2(M)

Rin Abe, Ayane Miyazaki, Takahiro Oyama, Mitsunori Araki, Shuro Takano, Nobuhiko Kuze, Yoshihiro Sumiyoshi, Koichi Tsukiyama, Yasuki Endo 1 Department of Chemistry, Tokyo University of Science, Japan 2 Department of Physics, College of Engineering, Nihon University, Japan 3 Department of Materials and Life Science, Sophia University, Japan 4 Division of Pure and Applied Science, Graduated School of Science and Technology, Gunma University, Japan 5 Department of Applied Chemistry, National Chiao Tung University, Taiwan