On the polarizabilities of centrosymmetric molecules: naphthalene as an example

Abstract The features of the Stark effect of centrosymmetric molecules in a static homogeneous electric field are discussed. Laser Stark spectroscopy has been performed on naphthalene molecules in a collimated, seeded supersonic beam. The Stark splitting and shifts of several rotational lines in the 8 1 0 band of the electronic 1 Bu 3u ← 1 A g transition could be measured in a static homogeneous electric field ranging up to 300 kV/cm. This is the first experimental determination of electronic excited-state static polarizabilities on a free polyatomic molecule. The polarizability anisotropies of the 1 B 3u excited state of naphthalene are P ′ aa − P ′ aa = 10.2 A 3 , P ′ bb − P ′ cc = 6.6 A 3 , and of the 1 A g ground state, P ″ aa − P ″ bb = 6.5 A 3 , P ″ bb − P ″ cc = 7.6 A 3 . In this experiment, only the difference of the average polarizability between these states can be determined, and was found to be Δ P = P ′ − P ″ = 1.6 A 3 .

[1]  A. Proutière.  Agreement between molecular polarizability anisotropies (γ2) deduced from Rayleigh light scattering and static Kerr birefringence in liquids—experimental and theoretical aspects , 1988 .

[2]  J. Muenter,et al.  Determination of the Polarizability Anisotropy of OCS by Microwave Spectroscopy , 1967 .

[3]  A. Hinchliffe,et al.  Ab initio calculation of the dipole polarizabilities of unsaturated hydrocarbons , 1980 .

[4]  P. J. Bounds,et al.  Effective molecular polarizabilities in some aromatic hydrocarbon crystals , 1977 .

[5]  A. Renn,et al.  Spectral hole burning in glasses and polymer films: the Stark effect , 1986 .

[6]  D. Margolese,et al.  Electric dipole moment of SO2 in ground and excited vibrational states , 1979 .

[7]  F. W. Birss,et al.  Computer assistance in the analysis of molecular spectra: I. Rotational structure of high resolution singlet-singlet bands , 1985 .

[8]  S. Golden,et al.  The Stark Effect for a Rigid Asymmetric Rotor , 1948 .

[9]  D. M. Hanson,et al.  The origin of Stark shifts and splittings in molecular crystal spectra. I. The effective molecular polarizability and local electric field: Durene and naphthalene , 1975 .

[10]  C. Maclean,et al.  Electric field N.M.R. , 1987 .

[11]  M. Zerner,et al.  Calculation of molecular polarizabilities for large systems within the random phase approximation , 1987 .

[12]  A. Schweig,et al.  Calculation of excited singlet and triplet state polarizabilities using the CNDO/S CI method. An application to naphthalene , 1975 .

[13]  J. Muenter,et al.  Stark and Zeeman properties of ozone from molecular beam spectroscopy , 1977 .

[14]  C. L. Cheng,et al.  Molecular polarizabilities from the Cotton-Mouton effect , 1972 .