Hi, I am using both Sarah and BasIreps to generate basis vectors to refinement the powder neutron diffraction data. However, I found there is some difference in the results I got.
1) For some specific space groups which has two choices of origin, there are corresponding options in origin to let me choose which space group to use. For instance, 141:1 or 141:2. However, in BasIreps, there is such an option. In this case, which one should I choose? Just use BasIreps or try the two space groups with Sarah? 2) The basis vectors generated by Sarah and BasIreps are different even with the same space group, k-vector and magnetic atom position. For example, space group, 141, k-vector 0.5 0.5 0.5, atomic position, 0 0 0. Sarah gives: SYMM X, Y, Z BASR 1 0 0 0 1 0 0 0 1 .71 0 0 0 -.7 0 0 0 -.7 BASI 0 0 0 0 0 0 0 0 0 .71 0 0 0 -.7 0 0 0 -.7 SYMM -X, -Y+1/2, Z BASR -1 0 0 0 -1 0 0 0 1 .71 0 0 0 -.7 0 0 0 .71 BASI 0 0 0 0 0 0 0 0 0 .71 0 0 0 -.7 0 0 0 .71 SYMM -Y+1/4, X+3/4, Z+1/4 BASR 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 BASI 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 SYMM Y+3/4, -X+3/4, Z+1/4 BASR 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 BASI 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 While BasIreps gives: SYMM x,y,z BASR 1 0 0 0 1 0 0 0 1 0 0 0 0 0 0 0 0 0 BASI 0 0 0 0 0 0 0 0 0 -1 0 0 0 1 0 0 0 1 SYMM -x+1/2,-y,z+1/2 BASR 0 0 0 0 0 0 0 0 0 -1 0 0 0 1 0 0 0 -1 BASI 1 0 0 0 1 0 0 0 -1 0 0 0 0 0 0 0 0 0 SYMM y+3/4,-x+1/4,-z+3/4 BASR 0 -1 0 1 0 0 0 0 -1 0 -1 0 -1 0 0 0 0 1 BASI 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 SYMM -y+3/4,x+3/4,-z+1/4 BASR 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 BASI 0 1 0 -1 0 0 0 0 -1 0 -1 0 -1 0 0 0 0 -1 Does anyone know how to choose the basis vector here? Best, Hellen
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