Hi, Professor David:
In zeolites, the Si atoms were replaced with Al atoms could generate the acidic sites, while the extra-framework-atoms are need to balance charges. However, when I substitute the Si atoms with Al atoms, the resulting structure, namely, Framework_0_final_*_*_*_P1.cif in the directory of Movies/System_0, does not obey the Lowenstein's rule (there exist the Al-O-Al linkage). While The corresponding .data file in the directory of Output/System_0 clearly mark out the "Lowentstein's rule obeyed by framework".
But, I do the calculation again, the resulting structure obey the Lowenstein's rule.
The followings are the simulation.input on the substitution:
SimulationType MonteCarlo
NumberOfCycles 0
Numberofintializtioncycles 0
PrintEvery 10
Forcefield GenericZeolites
RandomlySubstitute 6 Si Al
Framework 0
FrameworkName EAB
Unitcell 3 3 2
ExternalTemperature 298.0
#The EAB framework was removed the symmetry to P1 and remove all the Si atom were labelled as Si without the index number.