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arXiv · 1511.01430

Assessment of the LFAs-PBE exchange-correlation potential for high-order harmonic generation of aligned H2+ molecules

Hsiao-Ling Sun·Wei-Tao Peng·Jeng-Da Chai
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Abstract

We examine the performance of our recently developed LFAs-PBE exchange-correlation (XC) potential [C.-R. Pan, P.-T. Fang, and J.-D. Chai, Phys. Rev. A, 2013, 87, 052510] for the high-order harmonic generation (HHG) spectra and related properties of H2+ molecules aligned parallel and perpendicular to the polarization of an intense linearly polarized laser pulse, employing the real-time formulation of time-dependent density functional theory (RT-TDDFT). The results are compared with the exact solutions of the time-dependent Schrodinger equation as well as those obtained with other XC potentials in RT-TDDFT. Owing to its correct (-1/r) asymptote, the LFAs-PBE potential significantly outperforms conventional XC potentials for the HHG spectra and the properties that are sensitive to the XC potential asymptote. Accordingly, the LFAs-PBE potential, which has a computational cost similar to that of the popular Perdew-Burke-Ernzerhof (PBE) potential, can be very promising for the study of the ground-state, excited-state, and time-dependent properties of large electronic systems, extending the applicability of density functional methods for a diverse range of applications.

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Hsiao-Ling Sun, Wei-Tao Peng, Jeng-Da Chai. 2016-03-16. Assessment of the LFAs-PBE exchange-correlation potential for high-order harmonic generation of aligned H2+ molecules. https://doi.org/10.1039/c6ra03713e

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