The saturated ligand environment produced by various amino acids in 50% ethanol (v/v) around HoIII and TmIII ions have been studied with respect to hypersensitive transitions. The thermodynamics of hypersensitive transitions have been studied and correlated with spectral parameters. The thermodynamic parameters include work function, thermodynamic efficiency and partition functions of the said transitions. TmIII doped systems exhibit 80% thermodynamic efficiency where as HoIII doped systems show 89% efficiency.