title: Temperature dependent Raman and DFT study of creatine.
abstract: Temperature dependent Raman spectra of creatine powder have been recorded in the temperature range 420-100K at regular intervals and different clusters of creatine have been optimized using density functional theory (DFT) in order to determine the effect of temperature on the hydrogen bonded network in the crystal structure of creatine. Vibrational assignments of all the 48 normal modes of the zwitterionic form of creatine have been done in terms of potential energy distribution obtained from DFT calculations. Precise analysis gives information about thermal motion and intermolecular interactions with respect to temperature in the crystal lattice. Formation of higher hydrogen bonded aggregates on cooling can be visualized from the spectra through clear signature of phase transition between 200K and 180K.
authors.affiliation: Department of Physics, Banaras Hindu University, Varanasi 221005, India.
authors.forename: Debraj
authors.initials: D
authors.lastname: Gangopadhyay
authors.affiliation: Department of Physics, Banaras Hindu University, Varanasi 221005, India.
authors.forename: Poornima
authors.initials: P
authors.lastname: Sharma
authors.affiliation: Department of Physics, Banaras Hindu University, Varanasi 221005, India. Electronic address: ranjanksingh65@rediffmail.com.
authors.forename: Ranjan K
authors.initials: RK
authors.lastname: Singh
mesh_terms: D003401:Creatine / Q000737:chemistry*; D006860:Hydrogen Bonding; D008958:Models, Molecular; D011789:Quantum Theory; D013059:Spectrum Analysis, Raman / Q000379:methods*; D013696:Temperature
chemical_list: D003401:Creatine
keywords: Creatine; DFT; Hydrogen bonding; Temperature dependent Raman spectroscopy