#SET EXPORT ON in the CRYSTALS.SRT file? This 'exports' lists5,12 and 16 every time you close crystals down. They are all you need to use to get going agian from that point. Or You can re-name the CAMERON.L5I files created every time you run CAMERON to something more meaningful, then just issue #USE 'file.ext' to suck the atoms back into CRYSTALS if all goes wrong later OR You can type #PUNCH 5 (or 12 or 16) at any time, and the current LIST 5 (or 12 or 16) are appended to the current BETACRYS.PCH file. OR you can type #DISK RETAIN 5 Whenever you want to keep a copy of the current atoms in the .DSC file. "retained' lists are not deleted during a #PURGE. To get back to this, you just issue #DISK reset 5 xx where xx is the version number you want to reset to. OR you can issue #PURGE abc where 'abc' is a 3 letter file extension. CRYSTALS creates a file BETACRYS.ABC which is a copy of the active and retained lists in the .DSC file at that moment. Just move the BETACRYS.ABC file to anoper directory, rename it CRFILEV2.DSC, and you are away again. ================ Look in the NKET directory in WINCRYS. There is a file NKET.QCK. With a bit of modification, it can be made to re-create the .DSC file from scratch every time you start a structure, but by so doing you loose the flexibility of an adative data-base. However, you have to learn how to use the database. I've attached a modified NKET file, with the #SET EXPORT ON built into it rather than ask you to modify the CRYSTALS.SRT file. ================ # If you always use this file when you re-start CRYSTALS, you will # always find yourself importing the results from the last complete # job, even if you delete the .DSC file. You must keep the # NKET.REF file #set export on #QUICKSTART CELL 7.5330 7.5336 15.7802 SPACEGROUP P 41 CONTENT C 32 H 32 N 4 O 16 DATA 1.5418 FSQ FILE CRDIR:NKET.REF FORMAT (3F4.0, 2F8.2 ) END #LIST 5 READ NATOM = 13 ATOM C 1 X=0.819200 0.697300 0.118000 ATOM C 2 X=0.502300 0.661800 0.030100 ATOM C 3 X=0.809300 0.322200 0.053100 ATOM C 4 X=0.739400 0.046200 0.091800 ATOM C 5 X=0.936400 0.463600 0.025800 ATOM C 6 X=1.059800 0.461400 0.171800 ATOM C 7 X=0.836400 0.629600 0.033900 ATOM C 8 X=0.634800 0.560100 0.004300 ATOM C 9 X=1.106300 0.435500 0.091400 ATOM C 10 X=1.180100 0.263500 0.070100 ATOM C 11 X=1.048600 0.109000 0.096000 ATOM C 12 X=0.857800 0.160100 0.077100 ATOM C 13 X=0.630000 0.381500 0.040500 END #SFLS SCALE END #ANALYSE END #use export.dat