| Full text | |
| Author(s): |
Spada, Rene F. K.
;
Franco, Mauricio P.
;
Nieman, Reed
;
Aquino, Adelia J. A.
;
Shepard, Ron
;
Plasser, Felix
;
Lischka, Hans
Total Authors: 7
|
| Document type: | Journal article |
| Source: | Molecular Physics; v. N/A, p. 17-pg., 2022-06-24. |
| Abstract | |
In this work we discuss the calculation of the spin-density matrix from fundamental spin principles as implemented in the COLUMBUS Program System employing the graphical unitary group approach (GUGA). First, a general equation for the spin-density matrix is derived in terms of the one-and two-particle reduced density matrices, quantities that are spin-independent and readily available within the GUGA formalism. Next, the evaluation of this equation using the Shavitt loop values is discussed. Finally, the spatially resolved counterpart of the spin-density matrix, the spin distribution, is calculated for the phenalenyl radical and structures produced by heteroatoms with mono- and di-substitutions. The physical meaning of the spin-density along with its computational description using various methods is discussed putting special emphasis on negative contributions to the spin-density and their quantification via a spin-promotion index. (AU) | |
| FAPESP's process: | 19/07671-4 - Theoretical study of molecules in astrophysical environments |
| Grantee: | Rene Felipe Keidel Spada |
| Support Opportunities: | Regular Research Grants |