Graphical User Interface For Program FraGen

For the past few years, the crystal structure determination methods are rapidly developed with the widespread use of crystalline materials. The crystal structure determination methods are mainly reciprocal-space methods and real-space methods. Fra Gen(Framework Generator) is a computer model-building structure determination program in real space; it is used for structure determination and prediction of inorganic framework materials. Fra Gen is based on parallel tempering algorithm. Compared to similar methods across the world, it is more efficient by controlling Wyckoff Positions, searching balanced configuration, early exit from unpromising structures and supporting various restraints.An input file is needed for running Fra Gen. It is made of keywords and arguments. There are various kinds of keywords, and different keywords connect to different number and meaning of arguments. It is difficult to edit these keywords and arguments. Similar to other real-space methods, Fra Gen will produce thousands of structures. The atomic coordinates of these structures will be stored in the output file in the form of text. The process of analyzing these structures is complicated. Firstly, users need to copy the data of a structure from the output file; secondly, users need to analyze the data with a series of professional computer program, such as adding missing atoms, exporting general crystal file(like CIF, RES); finally, users have to visualize and analyze the structure by using the professional crystal software(like Materials Studio, Diamond). We developed the Input-GUI and the Output-GUI for Fra Gen in Python programming language in order to solve the above-mentioned problems.The Input-GUI included all the keywords used in Fra Gen. It classified the keywords with tabs and it can clearly display arguments related to keywords. Users don’t have to memorize the various keywords and arguments. With the Input-GUI, users can not only edit and save an input file conveniently, but also open an input file made before for reusing.The Output-GUI has the following features:(1) it can import all the structure data stored in the output file, add bridging O atoms for the structure automatically, and then display the structure. With the function of adding bridging O atoms, users can build whole structure models quickly for all the structures. With the Output-GUI, users can regulate the display range of the cell and change display styles of the structure; users can translate, zoom out and zoom in the displayed structure. Users can interact with the structure, such as displaying atom information, measuring atom distances and angels. The direct view of the structure allows users to check the structure directly for eliminating the unpromising structure.(2) Make simulated power XRD spectrum based on structure model. After the calculation of Fra Gen, a series of trial structures will be generated. The trial structures have to be compared with the experimental crystals to decide which one is the final structure, where the power XRD spectrum is needed. The function of making the power XRD spectrum is included in the Output-GUI. When the power XRD spectrum is generated, users can translate and zoom in the power XRD spectrum. And user can save picture of the power XRD spectrum.(3) Pick out topological unique structures based on coordination sequences by Fra Gen. There are a lot same topological structures among all the structures produced by Fra Gen. It is meaningless of analyzing all the structures and picking out topological unique structures is impossible by hand. The function of selecting topological unique structures makes it possible and efficient to process all the structure data together.Additionally, with the Output-GUI, users can edit the lattice parameters, delete unique atoms, export the general crystal structure file(CIF) and build structure model based on the general crystal structure file.The Input-GUI is convenient for making the input file by clarifying the keywords and clearly listed arguments. With the Output-GUI, the procedure of displaying and analyzing the structure is simplified; users can rapidly analyze all the structures together, which could improve the efficiency of processing the structure data.