loading page

A Systematic and Comparative Analysis of Four Major Classes of DFT Functionals to Compute Linear and Nonlinear Optical Properties of Benchmark Molecules
  • +2
  • Alina Waheed,
  • Shabbir Muhammad,
  • Mazhar Gilani,
  • Muhammad Adnan,
  • Zouhaier Aloui
Alina Waheed
COMSATS Institute of Information Technology - Lahore Campus
Author Profile
Shabbir Muhammad
King Khalid University

Corresponding Author:[email protected]

Author Profile
Mazhar Gilani
COMSATS Institute of Information Technology - Lahore Campus
Author Profile
Muhammad Adnan
Chosun University
Author Profile
Zouhaier Aloui
King Khalid University
Author Profile

Abstract

The present study spotlights the fundamental insights about the systematic and comparative analysis of four famous hybrid classes of density functional theory (DFT) methods and their efficacy to calculate the linear and nonlinear optical (NLO) polarizabilities. For this study, urea and para-nitroaniline (p-NA) molecular geometries are used as prototype to calculate their linear and NLO properties. For comparative purpose, these molecules are often used as reference organic molecules for determination of NLO response properties and there is a dire need of such benchmark database to be utilized by the researchers. We report systematically a range of functionals including hybrid (B3LYP, PBE1PBE, BHandHLYP), meta-hybrid (M06, M06-2X, M06-HF, M06-L), long-range corrected (CAM-B3LYP, LC-BLYP, LC-B97D, LC-B97D3) and functional with dispersion correction (ωB97, ωB97X, ωB97XD, HSEH1PBE). These groups are evaluated and their efficiency to calculate linear and NLO properties is graphically compared with each other. Overall, there is less deviations among different functionals for calculating dipole moments of p-NA and urea while these deviations enhance as one moves from dipole moment to linear polarizability and nonlinear hyperpolarizabilities. In general, if we look at the trends, the polarizability values of B3LYP, M06-L, CAM-B3LYP and HSEH1PBE are relatively large and can be compared with each other. The dispersion corrected and long-range corrected functional show more systematic deviations. For instance, among dispersion corrected functionals, the amplitudes of dipole moments, linear polarizability and NLO polarizabilities show an increasing trend as ωB97 < ωB97X < ωB97XD < HSEH1PBE. It is also important to note that LC-B97D and LC-B97D3 of long-range corrected functional have observed exactly the same values of all the calculated parameters. Thus, we believe that the current investigation will provide the benchmark data of reference NLO molecules at different methods for theoretical community and molecular level insights for experimental community to design better NLO materials for hi-tech NLO applications.