Laser spectroscopy of the electronic excited state or vibrationally excited state of  free  radicals such as the singlet-triplet interaction and the high-lying vibronic levels of the à state of C₃

Laser spectroscopy of the van der Waals complexes: the effect of the rare-gas atom on the Renner-Teller effect of C₃

Laser spectroscopy of metal-containing small carbon-chain clusters

Laser spectroscopy of high n-rydberg molecules by the pulsed electric field induced photo-ionization

“Laser-induced fluorescence spectroscopy of CCH( ) in vibrationally excited levels up to 4500cm^-1”, Yen-Chu Hsu et al., J. Chem. Phys. 103, 5919 (1995).

“Laser spectroscopy of CCH in the 36600-39700 cm^-1 region”, Whe-Yi Chiang and Yen-Chu Hsu, J. Chem. Phys. 111, 1454 (1999).

“The C₃-bending levels of the C₃-Ar complex studied by optical spectroscopy and ab initio calculation”, Guiqiu Zhang and Yen-Chu Hsu et al., J. Chem. Phys. 120, 3189 (2004).

“The 405-Å band of C₃ ( , 000-000): Perturbed low-J lines and lifetimes measurements”, Guiqiu Zhang and Yen-Chu Hsu et al., J. Chem. Phys. 122, 244308 ( 2005). 

“The bending vibrational levels of the acetylene cation: A case study of the Renner-Teller effects in a molecule with two degenerate bending vibrations”, Sheunn-Jiun Tang and Yen-Chu Hsu et al., J. Chem. Phys. 125, 133201(2006).