title: Vibrational spectroscopy, ab initio calculations and Frontier Orbital analysis of 4,5,6,8,9-pentachloropyrimido-[1,2-a][1,8]naphthyridin-10-one.
abstract: In this work we present a study of the vibrational spectra of 4,5,6,8,9-pentachloropyrimido-[1,2-a][1,8]naphthyridin-10-one, C11H2Cl5N3O, a substance belonging to the important pharmacological class of 1,8-naphthyridine derivatives. The Fourier transform infrared and the Fourier transform Raman spectra of the crystal were recorded at room temperature in the regions 400-4000 and 50-4000 cm(-1), respectively. Vibrational wavenumbers were predicted using Density Functional Theory calculations with the B3LYP functional on 6-31G(d,p) and 6-311++G(d,p) basis sets. The descriptions of the normal modes were made after calculating the potential energy distribution. Additionally, potential reaction sites were evaluated through Mulliken population and Frontier Orbital analysis.
authors.affiliation: Departamento de Física, Universidade Regional do Cariri, 63010-970, Brazil. Electronic address: carlosemidio@ymail.com.
authors.forename: C E S
authors.initials: CE
authors.lastname: Nogueira
authors.affiliation: Departamento de Física, Universidade Federal do Ceará, 60455-760, Brazil.
authors.forename: P E S
authors.initials: PE
authors.lastname: Caselli
authors.affiliation: Departamento de Física, Universidade Federal do Ceará, 60455-760, Brazil.
authors.forename: P T C
authors.initials: PT
authors.lastname: Freire
authors.affiliation: Departamento de Física, Universidade Regional do Cariri, 63010-970, Brazil.
authors.forename: A M R
authors.initials: AM
authors.lastname: Teixeira
authors.affiliation: Departamento de Física, Universidade Regional do Cariri, 63010-970, Brazil.
authors.forename: I M M
authors.initials: IM
authors.lastname: Oliveira
authors.affiliation: Departamento de Física, Universidade Federal de Mato Grosso, 78060-900, Brazil.
authors.forename: R R F
authors.initials: RR
authors.lastname: Bento
authors.affiliation: Departamento de Física, Universidade Federal de Mato Grosso, 78060-900, Brazil.
authors.forename: J L B
authors.initials: JL
authors.lastname: Faria
authors.affiliation: Universidade Estadual do Piauí, Teresina, PI 64002-150, Brazil; Departamento de Física, Universidade Federal do Ceará, 60455-760, Brazil.
authors.forename: G O M
authors.initials: GO
authors.lastname: Gusmão
authors.affiliation: Universidade Federal do Paraná, Setor Litoral, Matinhos 83260-000, Brazil.
authors.forename: L E
authors.initials: LE
authors.lastname: Silva
mesh_terms: D054879:Halogenation; D008958:Models, Molecular; D008968:Molecular Conformation; D009287:Naphthyridines / Q000737:chemistry*; D011743:Pyrimidines / Q000737:chemistry*; D011789:Quantum Theory; D017550:Spectroscopy, Fourier Transform Infrared; D013059:Spectrum Analysis, Raman
chemical_list: C574518:1,8-naphthyridin-2(1H)-one; D009287:Naphthyridines; D011743:Pyrimidines
keywords: C(11)H(2)Cl(5)N(3)O crystal; DFT; IR spectroscopy; Raman scattering