Theoretical surface-enhanced Raman spectra study of substituted benzenes I. Density functional theoretical SERS modelling of benzene and benzonitrile.
This paper reports a DFT modelling of SERS spectra for benzene and benzonitrile on the basis of a simple noncoordinate substrate-adsorbate model. Assignment of normal modes was obtained from internal force constants and potential energy distribution matrices and used to identify, according the SERS selection rules, the orientation of the optimized molecules on the metallic surface. Calculated band enhancements are in good agreement with experimental observations. The optimized geometry parameters of the molecule-Ag system, changes of HOMO-LUMO energies are discussed to give insight in the different SERS mechanisms for both molecules.
Fleming
Guillermo Diaz
GD
Department of Chemistry, Faculty of Sciences, University of Playa Ancha, Valparaiso, Casilla 34-V, Chile. ruben_diaz@entelchile.net
Golsio
Italo
I
Aracena
Andres
A
Celis
Freddy
F
Vera
Leticia
L
Koch
Rainer
R
Campos-Vallette
Marcelo
M
D001554:Benzene / Q000737:chemistry; D001555:Benzene Derivatives / Q000737:chemistry*; D008956:Models, Chemical; D009570:Nitriles / Q000737:chemistry; D009942:Organometallic Compounds / Q000737:chemistry; D011789:Quantum Theory; D012834:Silver / Q000737:chemistry; D013059:Spectrum Analysis, Raman / Q000379:methods; D013499:Surface Properties; D013816:Thermodynamics
D001555:Benzene Derivatives; D009570:Nitriles; D009942:Organometallic Compounds; D012834:Silver; C014356:benzonitrile; D001554:Benzene