Ciaffoni et al. reported the BE (1.68 ± 0.02 kcal mol -1 ) for H 2 S dimer where high-resolution diode laser spectroscopy has been applied for the detection of H 2 S at ppm level. They utilized different transitions within the region of the ν 1 + ν 2 + ν 3 and 2ν 1 + ν 2 combination bands around 1.58 µm. Using microwave spectroscopy, Das et al. provided the geometrical parameters (i.e., S-H•••S = 2.778(9)Å and ∠S-H•••S = 175(7)°) of the H 2 S dimer. Dreux et al. calculated the BE for H 2 S dimer at the CCSD(T)/ha(Q+d)Z (where ha(X+d)Z represents cc-pVQZ for H atoms and aug-cc-pV(Q+d)Z for S atoms) level to be 1.66 kcal mol -1 . Lemke carried out an extensive investigation using MP2, MP4, CCSD and CCSD(T) methods and showed that the BE of the H 2 S dimer at the CCSD(T)/CBS[D,T,Q] level of theory is 1.70 kcal mol -1 . Bandyopadhyay et al. studied the (H 2 S) n clusters (n = 2 -4) employing high-level quantum chemical calculations and calculated the BEs (1.67 kcal mol -1 ) at the CCSD(T)/CBS level with counterpoise corrected geometries at the MP2/aug-cc-pV(Q+d)Z level of theory. These values match excellently with the experimentally measured value by Ciaffoni et al. Compared to the water clusters, limited reports have been observed on the potential energy surface (PES) of (H 2 S) n clusters . Moreover, these studies show a remarkable difference in various aspects of the two types of clusters viz., H 2 O and H 2 S clusters; geometrically, energetically and in terms of non-covalent interactions (NCIs). For example, H 2 O tetramer prefers cyclic structure, whereas H 2 S tetramer prefers cage structure. Furthermore, Wategaonkar and coworkers have emphasized that dispersion plays a major role in generating a force of attraction in the O-H…S HB. Besides, this it is not yet clear how replacing individual monomeric moieties one at a time will progressively causes the pronounced change in appearance and stability of cluster. Therefore, a systematic analysis of (H 2 O) m (H 2 S) n mixed clusters would be beneficial to comprehend these modifications caused by the substitution of oxygen with sulphur or vice-versa.