From fc45705edb2bdd5104321db5d07a3e1936528889 Mon Sep 17 00:00:00 2001 From: chn Date: Mon, 26 May 2025 12:14:10 +0800 Subject: [PATCH] --- .../section/perfect/non-polar/default.typ | 21 ++++++++----------- 1 file changed, 9 insertions(+), 12 deletions(-) diff --git a/test-typst/section/perfect/non-polar/default.typ b/test-typst/section/perfect/non-polar/default.typ index ec7f4c5..06d913d 100644 --- a/test-typst/section/perfect/non-polar/default.typ +++ b/test-typst/section/perfect/non-polar/default.typ @@ -37,18 +37,15 @@ However, whether a mode is sufficiently strong to be experimentally visible // TODO: maybe it is better to assign Raman tensor to each bond, instead of atom -We propose a method to estimate the magnitudes of the Raman tensors of these phonons by symmetry analysis. -This method relies on the following two assumptions: -firstly, the change of polarizability caused by the movement of the atom in different locations - is mainly determined by its first- and second-nearest neighbors, - and the farther neighbors have relatively small contributions. -Secondly, the change of polarizability caused by Si atom and C atom is roughly connected by the reversal of the charge, - other factors (mass, bond length, etc.) contribute only a small value. -Therefore, the vibration mode with the most intense Raman intensity - could be estimated before the first-principle calculation and experiment, - and the Raman tensors of the calculated phonon modes could also be estimated - without further first-principle calculations. -Please see appendix for details. +We propose a method to estimate the magnitudes of the Raman tensors of these phonons based on symmetry analysis. +This approach is founded on the assumption that the change in polarizability induced by atomic displacements in 4H-SiC + is mainly determined by two factors: first- and second-nearest neighbors of the atom, and the symbol of charge corresponding to the atom, + all other factors (mass, bond length, etc.) contribute only a small value. +Consequently, + the phonon modes with the strongest Raman intensities can be predicted + prior to first-principles calculations and experiments, + and the Raman tensors of the calculated phonon modes can be estimated without additional first-principles computations. +Further details are provided in the appendix. The Raman tensors and frequencies of the negligible-polar phonons were calculated using first-principles methods, and the results are compared with experiment and theory (@table-nopol).