Formaldehyde-mediated spectroscopic properties of heavy water from first principles simulation

Publication date: Available online 28 October 2017 Source:Computational and Theoretical Chemistry Author(s): Vivek Kumar Yadav Water shows incredible ability to form a rich variety of hydrogen bonded structure when encountered atmospheric solute. We have presented a first-principle Born-Oppenheimer molecular dynamics simulation for deuterated formaldehyde-water ( D 2 CO - D 2 O ) system with dispersion corrected density functional (BLYP-D3). We explicitly focus on the relaxation and spectroscopy associated with the CO mode of D2CO and its interaction with surrounding water molecules through deuterated-hydrogen bonding. Our study enables us to compare and contrast our findings with earlier calculations on formaldehyde in water, and thereby explore the effect of solvent on the structural and dynamical properties of the solute. Inside the first solvation shell of deuterated formaldehyde, we find that the higher frequency of OD modes of water is a result of weak interaction. The frequency fluctuations of the CO mode of solute and OD modes of the solvent water are also investigated. Our calculation with the inclusion of dispersion correction in density functional produces much better results compared with the earlier ab initio approach [Mugnai et al., Mol. Phys. 105, 2203-2210 (2007)]. Graphical abstract

Source: Computational and Theoretical Chemistry - October 29, 2017 Category: Chemistry Source Type: research