The
conformational landscape of thioglycolic acid (TGA)
was investigated
by using the CCSD/cc-pVTZ level of theory. The GGC conformer was identified
as the global minimum, followed by the GAC conformer. The calculated
rotational constant for the GGC conformer exhibited good agreement
with the previously reported experimental results. Subsequently, the
study delved into the exploration of sulfur-centered hydrogen bonding
in TGA’s dimer and trimer clusters, employing the CCSD/cc-pVDZ
level of theory. These clusters revealed the participation of both
oxygen and sulfur atoms in noncovalent H-bonding, contributing to
their stability. The presence of these noncovalent interactions in
TGA clusters was elucidated through Atoms in Molecule (AIM), reduced
density gradient (RDG), and natural bond order (NBO) analysis, while
electrostatic potential (ESP) charge and vibrational mode analysis
further supported these findings.