Modeling Solvatochromism of a Quinolinium Betaine Dye in Water Solvent Using Sequential Hybrid QM/MM and Semicontinuum Approach
2011 (English)In: Journal of Physical Chemistry B, ISSN 1520-6106, E-ISSN 1520-5207, Vol. 115, no 5, 1056-1061 p.Article in journal (Refereed) Published
We have investigated the ambient temperature structure of 1-methyl-8-oxyquinolinium betaine (MOQB) in water solvent and compared to its gas-phase structure. We have employed Car-Parrinello molecular dynamics (CPMD) simulations within hybrid quantum mechanics molecular mechanics (QM/MM) framework to study MOQB in water while CPMD technique has been used for the gas phase. We report significant solvent-induced geometrical changes in MOQB. The dipole moment of MOQB in water is 2 times larger than the gas-phase value. The average absorption spectra calculated from gas-phase configurations using Coulomb attenuated-B3LYP (CAMB3LYP) level of theory is comparable with experimental spectra reported in benzene (lambda(max) = 590 nm), a nonpolar solvent. We have also computed the absorption spectra of MOQB in water solvent using continuum and semicontinuum solvent models. Based on this, we have calculated contributions from solvent-induced geometrical changes, hydrogen bonding, and intermolecular charge transfer to the solvatochromic shift and absorption spectra of MOQB in water. Absorption spectra calculations for MOQB in water with a semicontinuum approach for solvents using CAMB3LYP level of theory excellently reproduce the experimental spectra in water, where the theoretical lambda(max) is 433 nm and the experimental lambda(max) is around 440 nm.
Place, publisher, year, edition, pages
2011. Vol. 115, no 5, 1056-1061 p.
IdentifiersURN: urn:nbn:se:kth:diva-30895DOI: 10.1021/jp1049342ISI: 000286797700033ScopusID: 2-s2.0-79952845565OAI: oai:DiVA.org:kth-30895DiVA: diva2:404401
QC 201103172011-03-172011-03-072013-03-13Bibliographically approved