LLNL
Can CSLD get correct phonon dispersion of crystal with R3m phase
Hi, Dr Zhou. I read a series of your work about CSLD. I have tried to complete simulation on Si, NaCl and some crystals with tetragonal structure, and I got expected phonon dispersion, which matches to results from Phonopy. However, when I conducted on one material with R3m phase, I cannot get correct phonon dispersion. I am not sure that whether this software is confined to a particular crystalline phase such as cubic-like or tetragonal-like crystal or I made mistakes in some steps.
The following is my primitive cell where I used for calculated. Primitive cell 1.0 2.5606386051259404 1.4783853879668094 2.8923474905900837 -2.5606386051259404 1.4783853879668094 2.8923474905900837 0.0000000000000000 -2.9567707759336188 2.8923474905900837 1 1 direct 0.8403047127269900 0.8403047127269900 0.8403047127269900 0.1596952632730222 0.1596952632730222 0.1596952632730223
To get cubic like supercell, I use following sc.txt 3 -3 0 3 3 -6 3 3 3
I use csld.in below: prim = POSCAR sym_tol = 1E-3 epsilon_inf = epsilon_inf.txt
born_charge = born_charge.txt [model] model_type = LD cluster_in = clusters.out cluster_out = clusters.out symC_in = Cmat.mtx symC_out = Cmat.mtx max_order = 5 fractional_distance = False cluster_diameter = 10 8 5 4
[training] interface = VASP corr_type = f corr_in = Amat.mtx corr_out = Amat.mtx fval_in = fval.txt fval_out = fval.txt traindat1 = SPOSCAR dir_00000-disp0.01
[fitting] solution_in = solution_all solution_out = sol_2nd nsubset = 5 holdsize = 0.09 method = 5
mulist = 1E-5 1E-7 1E-9 1E-11 maxIter = 300 tolerance = 1E-6 subsetsize = 0.85 lambda = 0.5 uscale_list = 0.01
submodel1 = harmonic 0 1 2 [phonon] nac= 0
qpoint_fractional = False wavevector = [[50,[ 0,0,0],'\Gamma',[ 0.5,0.5, 0.5],'Z', [0, 0.5, 0.5],'F', [0, 0, 0],'\Gamma', [0, -0.371921, 0.371921],'X', [0, 0, 0.5],'L']] unit = meV
dos_grid = 15 15 15 nE_dos = 400 ismear= -1 epsilon = 0.05 pdos = True
thermal_T_range = 50 800 50 thermal_out = thermal_out.txt
[export_potential] export_shengbte = 4 4 4 2 3 4
[prediction] interface = VASP corr_type = f corr_in = Amat_pred.mtx corr_out = Amat_pred.mtx fval_in = fval_pred.txt fval_out = fval_pred.txt traindat0 = POSCAR traj*
##The result from CSLD
Please name the two elements in your POSCAR. Sorry. I add the name. The following is my primitive cell where I used for calculated. Primitive cell Ge1 Te1 1.0 2.5606386051259404 1.4783853879668094 2.8923474905900837 -2.5606386051259404 1.4783853879668094 2.8923474905900837 0.0000000000000000 -2.9567707759336188 2.8923474905900837 Ge Te 1 1 direct 0.8403047127269900 0.8403047127269900 0.8403047127269900 Ge 0.1596952632730222 0.1596952632730222 0.1596952632730223 Te