Dear Hiphive users,
Recently, I have been trying to reconstruct a 2nd order force constant by using hiphive. But after running the program, after a while, the program stops by showing the following error :
Primitive cell:
Formula: XYZ
Cell:
[ 0.00000 3.67966 0.04826]
[ -4.25402 0.00000 0.00000]
[ 0.00000 -1.97664 21.74727]
Basis:
X [ 0.30741 0.33031 0.48902]
X [ 0.69259 0.66969 0.51098]
X [ 0.30741 0.66969 0.48902]
…
Crystal symmetry:
Spacegroup: P2/m (10)
Unique site: 2
Symmetry operations: 4
symprec: 1.00e-05
Cutoffs:
Maximum cutoff: 6.517468246869091
Found 6 center atoms with 70 images totaling 76 atoms
Clusters:
Clusters: {2: 277, 3: 3788}
Total number of clusters: 4065
Orbits:
Orbits: {2: 50, 3: 395}
Total number of orbits: 445
Eigentensors:
Eigentensors: {2: 366, 3: 9716}
Total number of parameters: 10082
Constraints:
Acoustic: True
Number of degrees of freedom: {2: 353, 3: 8798}
Total number of degrees of freedom: 9151
Force constant reconstruction error order 2: 3.3643%
Traceback (most recent call last):
File “invariance-fc2.py”, line 22, in
parameters = extract_parameters(fcs2, cs)
File “/home/.local/lib/python3.7/site-packages/hiphive/utilities.py”, line 353, in extract_parameters
fc_original = fcs.get_fc_array(order=order)
File “/home/.local/lib/python3.7/site-packages/hiphive/force_constants.py”, line 116, in get_fc_array
raise ValueError(‘Order not in orders’)
ValueError: Order not in orders
I have never encountered this type of error before. The material is a 2D material and I have used phonopy for phonon calculation. Can anyone suggest to me what I should do in order to resolve this issue.
Thank you in advance,
Regards,
Dr. Suman Chowdhury