title: Normal co-ordinate analysis, molecular structural, non-linear optical, second order perturbation studies of Tizanidine by density functional theory.
abstract: The spectroscopic techniques and semi-empirical molecular calculations have been utilized to analyze the drug Tizanidine (5CDIBTA). The solid phase Fourier Transform Infrared (FTIR) and Fourier Transform Raman (FTR) spectral analysis of 5CDIBTA is carried out along with density functional theory (DFT) calculations (B3LYP) with the 6-311++G(d,p) basis set. Detailed interpretation of the vibrational spectra of the compound has been made on the basis of the calculated potential energy distribution (PED). The individual atomic charges by NPA using B3LYP method is studied. A study on the Mulliken atomic charges, frontier molecular orbitals (HOMO-LUMO), molecular electrostatic potential (MEP) and thermodynamic properties were performed. The electric dipole moment (μ) and the first hyperpolarizability (α) values of the investigated molecule were also computed.
authors.affiliation: Department of Applied Physics, Sri Venkateswara College of Engineering, Sriperumbudur 602105, India.
authors.forename: N R
authors.initials: NR
authors.lastname: Sheela
authors.affiliation: Department of Applied Physics, Sri Venkateswara College of Engineering, Sriperumbudur 602105, India. Electronic address: muthu@svce.ac.in.
authors.forename: S
authors.initials: S
authors.lastname: Muthu
authors.affiliation: Department of Applied Physics, Sri Venkateswara College of Engineering, Sriperumbudur 602105, India.
authors.forename: S
authors.initials: S
authors.lastname: Sampathkrishnan
authors.affiliation: Department of Chemistry, King Fahd University of Petroleum & Minerals, Dhahran 31261, Saudi Arabia.
authors.forename: Abdulaziz A
authors.initials: AA
authors.lastname: Al-Saadi
mesh_terms: D003000:Clonidine / Q000031:analogs & derivatives* / Q000737:chemistry; D004583:Electrons; D008958:Models, Molecular; D008968:Molecular Conformation; D017711:Nonlinear Dynamics; D055620:Optical Phenomena; D011789:Quantum Theory; D017550:Spectroscopy, Fourier Transform Infrared; D013059:Spectrum Analysis, Raman; D055672:Static Electricity; D013816:Thermodynamics; D014732:Vibration
chemical_list: C023754:tizanidine; D003000:Clonidine
keywords: DFT; FT-Raman; FTIR; MEP; NBO