*variable goodBonds
Meaning: specifies the minimum bond valence matrix (i.e. the ratio valence/coordination number, extended by Brown’s formula) in this system – this does not have to be accurate, just give a reasonable guess. Like the IonDistances matrix (see below), this is square keymatrix cast in an upper-triangular form.
Default: 0.15
Format:
% goodBonds
1.0 1.0 0.2
0.0 1.0 0.5
0.0 0.0 1.0
% EndGoodBonds
Notes: The dimensions of this matrix must be equal either to the number of atomic species or unity. If only one number is used, the matrix is filled with this number. The matrix above reads as follows: to be considered a bond, the Mg-Mg distance should be short enough to have bond strength of 1.0 or more, the same for Mg-Si, Si-Si and O-O bonds (by using such exclusive criteria, we effectively disregard these interactions as potential bonds), whereas the weakest Mg-O bond that will be considered for hardness and softmutation calculations will have valence strength of 0.2, and Si-O will have strength of 0.5 or more. To set this parameter just take values close to the ratio valence/(maximum possible coordination number). Easy!
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