Dynamic Polarizability and Higher-Order Electric Properties of Fluorene, Carbazole, and Dibenzofuran

Abstract

Static electric properties, from the dipole moment to the second-hyperpolarizability tensor γ, of the 3membered, isoelectronic ring molecules, fluorene (FL), carbazole (CR), and dibenzofuran (DBF), have been calculated at various levels of approximation. The electron correlation effects have been included at the coupled-cluster (CC) level, using CCSD and CC2 versions of the method. DFT calculations with the CAM-B3LYP functional have also been performed, and the results are compared to the CC values. The electric property-tailored Pol basis set and its more compact Z3Pol version have been employed in all static calculations. Differences between dipole polarizability values computed at the Pol and Z3Pol bases have been found to be almost negligible. Therefore, all components of the frequency-dependent dipole polarizability tensor α(−ω;ω) have been determined at the CAM-B3LYP/Z3Pol level. Divergence occurring at electronic resonances has been eliminated using the complex polarization propagator (CPP) formalism, explicitly introducing an imaginary iΓ parameter to account approximately for the finite lifetime of the excited state. The imaginary part of the dipole polarizability Im α(−ω;ω) has been calculated for a wide range of external radiation energies up to 10 eV, and its maxima have been compared to the calculated vertical electronic excitation energies.

Local energy decomposition analysis and molecular properties of encapsulated methane in fullerene (CH4@C60)

“…To inspect these effects for the CH 4 @C 60 endohedral complex, the dipole polarizabilities of CH 4 , C 60 , and CH 4 @C 60 were calculated at the CAM-B3LYP/Sadlej-pVTZ level of theory. The rangeseparated and Coulomb-attenuating method called as the CAM-B3LYP DFT approximation 94 was shown to deliver accurate polarizabilities, 95 and a balanced description of electronic excited states. 96 The Sadlej-pVTZ basis set was specifically developed for calculations of polarizabilities and other electric molecular properties.…”

Local Energy Decomposition Analysis and Molecular Properties of Encapsulated Methane in Fullerene (CH4@C60)

“…To inspect these effects for the CH 4 @C 60 endohedral complex, the dipole polarizabilities of CH 4 , C 60 , and CH 4 @C 60 were calcu-lated at the CAM-B3LYP/Sadlej-pVTZ level of theory. The rangeseparated and Coulomb-attenuating method called as the CAM-B3LYP DFT approximation 91 was shown to deliver accurate polarizabilities, 92 and a balanced description of electronic excited states. 93 The Sadlej-pVTZ basis set was specifically developed for calculations of polarizabilities and other electric molecular properties.…”

Benchmarking anisotropic polarizabilities for 14 (hetero)‐aromatic molecules at RPA, RPA(D), HRPA, HRPA(D), SOPPA, SOPPA(CC2), SOPPA(CCSD), CC2, CCSD and CC3 levels

“…It is fair to say that the anisotropic polarizability in itself, together with the off‐diagonal elements of the polarizability tensor, is a subject which has been rather overlooked. Meanwhile the isotropic polarizabilities have received much attention, especially in benchmark studies [2–28]. A full description of studies of isotropic polarizabilities would be too long so only a few honorable mentions are made.…”

“…Various levels of coupled cluster theory have been applied to the calculation of isotropic polarizabilities [2–13, 16, 27]. In 1998, for example, Larsen et al [8] benchmarked the coupled cluster methods CCS, CC2 and CCSD for isotropic polarizabilities.…”

“…They did in general not find any difference in the performance of the methods for anisotropic polarizabilities, yet it was found that for smaller molecules the results deviated less from experimental data than for larger aromatic systems. DFT with the functional CAM‐B3LYP has also been tested against CC2 and CCSD in a study from 2019 [13]. The polarizability tensor components were presented as well as both the isotropic and anisotropic polarizability and the anisotropy was found to correlate with the decreasing aromaticity.…”