Theoretical Insights into Hydrogen Bonding and Its Influence on the Structural and Spectral Properties of Aquo Palladium(II) Complexes: cis-[(dppp)Pd(H2O)2]2+, cis-[(dppp)Pd(H2O)(OSO2CF3)]+(OSO2CF3)-, and cis-[(dppp)Pd(H2O)2]2+(OSO2CF3)2-

Density functional theory (DFT) and time-dependent density functional theory (TDDFT) methods have been performed to investigate the ground and excited states of aquo palladium(II) complexes cis-[(dppp)Pd(H2O)(2)](2+), cis-[(dppp)Pd(H2O)(OSO2CF3)](+) (OSO2CF3)(-), and cis-[(dppp)Pd(H2O)(2)](2+)(OSO2CF3)(2)(-). Insights into the influence of hydrogen bonding on the structural and spectral properties of these three aquo Pd(II) complexes are presented. The structures and the HOMO-LUMO energy gap of the three aquo Pd(II) complexes can be markedly influenced by hydrogen bonding interactions. Hydrogen bonds can also significantly influence their absorption spectra.