Noncollinear and Spin-Flip TDDFT in Multicollinear Approach.
J Chem Theory Comput
; 19(8): 2270-2281, 2023 Apr 25.
Article
in En
| MEDLINE
| ID: mdl-36971474
ABSTRACT
Time-dependent density functional theory (TDDFT) is one of the most important tools for investigating the excited states of electrons. The TDDFT calculation for spin-conserving excitation, where collinear functionals are sufficient, has obtained great success and has become routine. However, TDDFT for noncollinear and spin-flip excitations, where noncollinear functionals are needed, is less widespread and still a challenge nowadays. This challenge lies in the severe numerical instabilities that root in the second-order derivatives of commonly used noncollinear functionals. To be free from this problem radically, noncollinear functionals with numerical stable derivatives are desired, and our recently developed approach, called the multicollinear approach, provides an option. In this work, the multicollinear approach is implemented in noncollinear and spin-flip TDDFT, and prototypical tests are given.
Full text:
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Database:
MEDLINE
Language:
En
Journal:
J Chem Theory Comput
Year:
2023
Type:
Article