Effect of Medium Polarity on the Second-Order Polarizability of an Octupolar Chromophore: An ab initio Reaction Field Study of Triaminotrinitrobenzene

• Published in: European journal of organic chemistry Vol. 1998; no. 7; pp. 1267 - 1269
• Main Authors: Dehu, Christophe, Geskin, Victor, Persoons, André, Brédas, Jean-Luc
• Format: Journal Article
• Language: English
• Published: Weinheim WILEY-VCH Verlag GmbH 01.07.1998; WILEY‐VCH Verlag GmbH
• Subjects: Nonlinear optics (NLO); Octupolar NLO chromophore; Second-order polarizability; Self-consistent reaction field (SCRF); Triaminotrinitrobenzene
• ISSN: 1434-193X; 1099-0690
• DOI: 10.1002/(SICI)1099-0690(199807)1998:7<1267::AID-EJOC1267>3.0.CO;2-T

The Self‐Consistent Reaction Field theory (extended to include an ellipsoidal cavity for the solute and a multipolar expansion of the field) is used to investigate the influence of medium polarity on the second‐order nonlinear optical response of the prototypical octupolar compound 1,3,5‐triamino‐2,4,6‐trinitrobenzene, TATB. Despite the absence of any dipole moment in TATB, the effect of medium polarity is found to be significant; for instance, the βzzz tensor component of TATB is calculated to be twice as large in dichloromethane (electric permittivity ϵ = 9.1) as in the gas phase (ϵ = 1). This enhancement factor is similar to, though somewhat smaller than the one calculated for the dipolar counterpart of TATB, i.e. p‐nitroaniline.