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Jahn-Teller tensorial force constants

Jahn-Teller tensorial forces can be treated in an analogous way. The parameters Tens_JT has to be specified in the same way as Tens_P, Tens_S, Tens_T but in addition one has to add for each interaction two vectors that are used to calculated the JT factor: this factor is given by the product of two sines having as arguments the scalar product of $Q$ and the vectors. The JT model is activated by setting the variable USE_JT in the input file for dispersionDeb.py :

USE_JT=1
the way to input the vectors for the JT factor is shown as follows :
B_JT=100000.0
a=3.95
b=a
Tens_JT={}
Tens_JT['O_G0'] = {}
Tens_JT ['O_G0']['O_G0']= [
                           [    
                             Numeric.array([a/2.0,b/2.0,0]),
                             Numeric.array([[0,B_JT,0.0],
                                            [0,0,0.0],
                                            [0,0,0.0]] ),
                             Numeric.array([a/2.0,0,0]),
                             Numeric.array([0,b/2.0,0])
                           ], 
                           [    
                             Numeric.array([a,0,0]),
                             Numeric.array([[-B_JT,0.0,0.0],
                                            [0,0,0.0],
                                            [0,0,0.0]] ),
                             Numeric.array([a/2.0,0,0]),
                             Numeric.array([a/2.0,0,0])
                           ]
                         ]

where the vectors follows the $3X3$ tensor.



Alessandro Mirone 2003-11-17