Symmetry-adapted perturbation theory interaction energy decomposition for H2CY-XF (Y = O, S, Se; X = H, Li, Cl) complex

The H2CY-XF (Y = O, S, Se; X = H, Li, Cl) complexes have been investigated at the MP2(Full)/aug-cc-pVTZ level. The formation and structures of hydrogen, lithium, and chloride bonds were studied comparatively with electrostatic potentials. The hydrogen and lithium bonds become weaker in the order O < S < Se, while the chloride bond becomes stronger in the same order. The lithium bond is the strongest in all complexes. The chloride bond is weaker than the hydrogen bond in the H2CO complex, while the former is stronger than the latter in the H2CS and H2CSe complexes. The nature of three types of interactions in these complexes has been analyzed with symmetry-adapted perturbation theory (SAPT) method.