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Cofer-Shabica DV, Athavale V, Subotnik JE. To guess or not to guess excited state amplitudes during optimization and dynamics. J Chem Phys 2023; 159:121101. [PMID: 38127368 DOI: 10.1063/5.0163571] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/17/2023] [Accepted: 08/28/2023] [Indexed: 12/23/2023] Open
Abstract
We report robust initial guesses for the amplitudes and z-vectors in a configuration interaction singles or Tamm-Dancoff approximation calculation that consistently reduce the total number of iterations required for an excited state calculation often by over 50%. The end result of these guesses is that the practicing chemist can expect to generate excited state optimized structures with a total wall time reduced by as much as 30% in the future without any approximations-simply by using information gathered at one geometry and applying it to another geometry.
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Affiliation(s)
- D Vale Cofer-Shabica
- Chemistry, University of Pennsylvania, 231S. 34 Street, Cret Wing 141D, Philadelphia, Pennsylvania 19104-6243, USA
| | - Vishikh Athavale
- Chemistry, University of Pennsylvania, 231S. 34 Street, Cret Wing 141D, Philadelphia, Pennsylvania 19104-6243, USA
| | - Joseph E Subotnik
- Chemistry, University of Pennsylvania, 231S. 34 Street, Cret Wing 141D, Philadelphia, Pennsylvania 19104-6243, USA
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Liang W, Pei Z, Mao Y, Shao Y. Evaluation of molecular photophysical and photochemical properties using linear response time-dependent density functional theory with classical embedding: Successes and challenges. J Chem Phys 2022; 156:210901. [DOI: 10.1063/5.0088271] [Citation(s) in RCA: 2] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/04/2023] Open
Abstract
Time-dependent density functional theory (TDDFT) based approaches have been developed in recent years to model the excited-state properties and transition processes of the molecules in the gas-phase and in a condensed medium, such as in a solution and protein microenvironment or near semiconductor and metal surfaces. In the latter case, usually, classical embedding models have been adopted to account for the molecular environmental effects, leading to the multi-scale approaches of TDDFT/polarizable continuum model (PCM) and TDDFT/molecular mechanics (MM), where a molecular system of interest is designated as the quantum mechanical region and treated with TDDFT, while the environment is usually described using either a PCM or (non-polarizable or polarizable) MM force fields. In this Perspective, we briefly review these TDDFT-related multi-scale models with a specific emphasis on the implementation of analytical energy derivatives, such as the energy gradient and Hessian, the nonadiabatic coupling, the spin–orbit coupling, and the transition dipole moment as well as their nuclear derivatives for various radiative and radiativeless transition processes among electronic states. Three variations of the TDDFT method, the Tamm–Dancoff approximation to TDDFT, spin–flip DFT, and spin-adiabatic TDDFT, are discussed. Moreover, using a model system (pyridine–Ag20 complex), we emphasize that caution is needed to properly account for system–environment interactions within the TDDFT/MM models. Specifically, one should appropriately damp the electrostatic embedding potential from MM atoms and carefully tune the van der Waals interaction potential between the system and the environment. We also highlight the lack of proper treatment of charge transfer between the quantum mechanics and MM regions as well as the need for accelerated TDDFT modelings and interpretability, which calls for new method developments.
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Affiliation(s)
- WanZhen Liang
- State Key Laboratory of Physical Chemistry of Solid Surfaces, Collaborative Innovation Center of Chemistry for Energy Materials, Fujian Provincial Key Laboratory of Theoretical and Computational Chemistry, and Department of Chemistry, College of Chemistry and Chemical Engineering, Xiamen University, Xiamen 361005, People’s Republic of China
| | - Zheng Pei
- State Key Laboratory of Physical Chemistry of Solid Surfaces, Collaborative Innovation Center of Chemistry for Energy Materials, Fujian Provincial Key Laboratory of Theoretical and Computational Chemistry, and Department of Chemistry, College of Chemistry and Chemical Engineering, Xiamen University, Xiamen 361005, People’s Republic of China
| | - Yuezhi Mao
- Department of Chemistry, Stanford University, Stanford, California 94305, USA
| | - Yihan Shao
- Department of Chemistry and Biochemistry, University of Oklahoma, Norman, Oklahoma 73019, USA
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3
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Herr JD, Steele RP. Accelerating ab initio molecular dynamics simulations by linear prediction methods. Chem Phys Lett 2016. [DOI: 10.1016/j.cplett.2016.08.050] [Citation(s) in RCA: 3] [Impact Index Per Article: 0.4] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 10/21/2022]
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Fang J, Gao X, Song H, Wang H. On the existence of the optimal order for wavefunction extrapolation in Born-Oppenheimer molecular dynamics. J Chem Phys 2016; 144:244103. [PMID: 27369493 DOI: 10.1063/1.4954234] [Citation(s) in RCA: 6] [Impact Index Per Article: 0.8] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/14/2022] Open
Abstract
Wavefunction extrapolation greatly reduces the number of self-consistent field (SCF) iterations and thus the overall computational cost of Born-Oppenheimer molecular dynamics (BOMD) that is based on the Kohn-Sham density functional theory. Going against the intuition that the higher order of extrapolation possesses a better accuracy, we demonstrate, from both theoretical and numerical perspectives, that the extrapolation accuracy firstly increases and then decreases with respect to the order, and an optimal extrapolation order in terms of minimal number of SCF iterations always exists. We also prove that the optimal order tends to be larger when using larger MD time steps or more strict SCF convergence criteria. By example BOMD simulations of a solid copper system, we show that the optimal extrapolation order covers a broad range when varying the MD time step or the SCF convergence criterion. Therefore, we suggest the necessity for BOMD simulation packages to open the user interface and to provide more choices on the extrapolation order. Another factor that may influence the extrapolation accuracy is the alignment scheme that eliminates the discontinuity in the wavefunctions with respect to the atomic or cell variables. We prove the equivalence between the two existing schemes, thus the implementation of either of them does not lead to essential difference in the extrapolation accuracy.
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Affiliation(s)
- Jun Fang
- Institute of Applied Physics and Computational Mathematics, Beijing, China
| | - Xingyu Gao
- Institute of Applied Physics and Computational Mathematics, Beijing, China
| | - Haifeng Song
- Institute of Applied Physics and Computational Mathematics, Beijing, China
| | - Han Wang
- Institute of Applied Physics and Computational Mathematics, Beijing, China
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Gerber RB, Shemesh D, Varner ME, Kalinowski J, Hirshberg B. Ab initio and semi-empirical Molecular Dynamics simulations of chemical reactions in isolated molecules and in clusters. Phys Chem Chem Phys 2014; 16:9760-75. [DOI: 10.1039/c3cp55239j] [Citation(s) in RCA: 33] [Impact Index Per Article: 3.3] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 02/04/2023]
Abstract
Recent progress in “on-the-fly” trajectory simulations of molecular reactions, using different electronic structure methods is discussed, with analysis of the insights that such calculations can provide and of the strengths and limitations of the algorithms available.
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Affiliation(s)
- R. B. Gerber
- Institute of Chemistry and The Fritz Haber Research Center
- The Hebrew University of Jerusalem
- Jerusalem 91904, Israel
- Department of Chemistry
- University of California
| | - D. Shemesh
- Institute of Chemistry and The Fritz Haber Research Center
- The Hebrew University of Jerusalem
- Jerusalem 91904, Israel
| | - M. E. Varner
- Department of Chemistry
- University of California
- Irvine 92697, USA
| | - J. Kalinowski
- Department of Chemistry
- University of Helsinki
- , Finland
| | - B. Hirshberg
- Institute of Chemistry and The Fritz Haber Research Center
- The Hebrew University of Jerusalem
- Jerusalem 91904, Israel
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6
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Steele RP. Communication: Multiple-timestep ab initio molecular dynamics with electron correlation. J Chem Phys 2013; 139:011102. [DOI: 10.1063/1.4812568] [Citation(s) in RCA: 20] [Impact Index Per Article: 1.8] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/15/2023] Open
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