Bond_Str

The program Bond_Str calculates distances and angles in crystal structures. It is based in old Fortran77 versions but is has been completely re-written and it is now based in CrysFML (Crystallographic Fortran95 Modules Library). CrysFML contains in its "Atom_Module" (in file CFML_Atom_Mod.f90), procedures making all calculations. The main program calls the two procedures "Calc_Dist_Angle_Sigma" and "Calc_BVS" to perform the calculations.

The most reliable bond-valence parameters (based in the file bvparm.cif from I.D. Brown) are stored in CFML_BVpar.f90, but, alternatively, user-given bond-valence parameters can be read form the input file instead of using the internal parameters.

The program needs an input file that can be either a standard CIF file or a CFL file containing just the necessary structural information and the ionic species. A CFL file is a file with a format that is recognized by all programs based in CrysFML. They have the extension *.cfl and are in free format. The different items are recognized thanks to keywords. A CFL file can be generated from a CIF file just running Bond_Str.

Alternatively, the GUI GBond_Str program can be used directly to convert CIF files to CFL files. Remember that information about the chemical species (ionic oxidation states) is not always included in CIF files, so the user has to include it in the appropriate place in the atom string if he(she) wants to make bond-valence.

calculations. The program can be invoked from the command line together with the code (name without extension) of a CIF or CFL file. The program looks first for the existence of a CFL file with the given code, if there is no CFL file it looks for a CIF file.

 

Notes about the GUI GBond_Str

The program GBond_Str is a GUI for running Bond_Str without direct editing the input file. The interface has only a single window, except when the internal editor is invoked to visualise the results.

Notice that the user can provide bond-valence parameters by filling the appropriate box that is activated as soon as one increases the number of user-given bond-valence parameter that is initially put to zero.

The program GBond_Str is just a tool for manipulating CIF and CFL files. There is no calculation inside GBond_Str. When the user clicks on the run button (or select Run in the menu) the program saves the current CFL file and invokes Bond_Str with the code of the current file as argument. The normal output of Bond_Str that is directed to the screen when run in a DOS-like window shell is not seen. As soon as Bond_Str finishs the calculations GBond_Str takes the control and edit the output file from Bond_Str.