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Abstract Raman scattering is performed on Fe3GeTe2(FGT) at temperatures from 8 to 300 K and under pressures from the ambient pressure to 9.43 GPa. Temperature‐dependent and pressure‐dependent Raman spectra are reported. The results reveal respective anomalous softening and moderate stiffening of the two Raman active modes as a result of the increase of pressure. The anomalous softening suggests anharmonic phonon dynamics and strong spin–phonon coupling. Pressure‐dependent density functional theory and phonon calculations are conducted and used to study the magnetic properties of FGT and assign the observed Raman modes,and. The calculations proved the strong spin–phonon coupling for themode. In addition, a synergistic interplay of pressure‐induced reduction of spin exchange interactions and spin–orbit coupling effect accounts for the softening of themode as pressure increases.
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Optical Activity of Spin‐Forbidden Electronic Transitions in Metal Complexes from Time‐Dependent Density Functional Theory with Spin‐Orbit Coupling
Abstract The calculation of magnetic transition dipole moments and rotatory strengths was implemented at the zeroth‐order regular approximation (ZORA) two‐component relativistic time‐dependent density functional theory (TDDFT) level. The circular dichroism of the spin‐forbidden ligand‐field transitions of tris(ethylenediamine)cobalt(III) computed in this way agrees very well with available measurements. Phosphorescence dissymmetry factorsand the corresponding lifetimes are evaluated for three N‐heterocyclic‐carbene‐based iridium complexes, two of which contain helicene moieties, and for two platinahelicenes. The agreement with experimental data is satisfactory. The calculations reproduce the signs and order of magnitude of, and the large variations of phosphorescence lifetimes among the systems. The electron spin contribution to the magnetic transition dipole moment is shown to be important in all of the computations.
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- Award ID(s):
- 1855470
- PAR ID:
- 10372297
- Publisher / Repository:
- Wiley Blackwell (John Wiley & Sons)
- Date Published:
- Journal Name:
- ChemistryOpen
- Volume:
- 11
- Issue:
- 5
- ISSN:
- 2191-1363
- Format(s):
- Medium: X
- Sponsoring Org:
- National Science Foundation
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