|JSV1.07 runs also on Linux It can also calculate Xray diffraction intensities. The Diffraction Viewer module XRDL allows the 3D/2D display of the diffraction pattern. You can view 0.layers while rotating the 3D pattern in real time or scan along some axis to see higher order layers only. (very useful for people interested in precession or electron diffraction simulations !) Also Laue patterns are possible in real time rotation. (useful for finding effect of misalignment)|
This page introduces JSV (Java Structure Viewer) , which I am presently developing as a stand-alone application. In order to run it you will need to have a Java Virtual Machine (JVM) installed on your computer wich can be downloaded for free in form of © Sun Microsystem's JDK 1.2 . Then you can use either the "java" command or the "jre" (Java Runtime Environment) command to execute JSV.
You might ask "why Java and not VRML?", since everybody knows that VRML gives very nice display quality for crystal structures. Well, it has some disadvantages, too. It is easy to convert a set of cartesian data into VRML data, but if you only have unit cell data, then you need some software to generate the atom positions first. Some commercial programs do that (e.g.: ATOMS). VRML can be viewed in a webbrowser with a VRML plug-in, which you need to install first or with a separate stand-alone VRML viewer (GLView3.6). When viewing VRML you are not able to measure atom distances and angles by clicking at them or switch the display of atom labels on and of. Therefore if one does not only limit oneself to simply displaying a structure a separate program becomes necessary. That's why I am writing JSV. I personally want to use it for displaying quasicrystal structures where at least 1000 atoms might be needed for a representative region. Using the VRML browsers I found it annoying that I cannot switch to orthonormal projection. For so many atoms this is a very welcome feature.
One of the major tasks for future updates will be to implement the new Java3D libraries which will enable JSV to display real 3D-graphics (similar to VRML) in contrast to the 2D- or pseudo3D-graphics it uses now.
Any comments and suggestions on JSV are welcome. User feedback is desired so that I see if there is any interest in JSV at all, which might be a motivation to speed up my efforts to improve it. After all, JSV is only one of several hobby projects of mine.
The Java codes in this package are obfuscated to prevent reverse engineering.
Click here to see screen shots of JSV's components
download Java Interpreter
download Java3D for JDK1.2
JSV input files DO NOT NEED to have a file extension (eg. *.jsv) . However I recommend to use them, since that allows you to associate these files with jsv.bat (under Windows) for automatically starting JSV when you double click a *.jsv file. The *.SDF files (Structure Description File) which are created by JSV NEED the extension *.SDF !
At present JSV only supports tetrahedra and octahedra. (squares, cubes, triangles may be created for VRML output, but they will be incorrectly displayed within JSV)
Please let me know if anyone of you has tested JSV successfully on SOLARIS or a LINUX distribution other than RedHat5.2.
Note : A major criterion for performance of a JAVA program is RAM. You need a minimum of 32Mb RAM, although 64 is better.
Hint: On some systems like LINUX the JVM (Java Virtual Machine) may use a default heap memory size of only 12-14 Mbyte. If you have more RAM then you can specify new minimum and maximum heap sizes using the -Xms and -Xmx options (eg. java -Xms12m -Xmx32m JSV , for using 12-32 Mbyte) As mentioned above you may also use the jre command instead of the java tool.
Windows: Windows users may just execute the provided batch files to start JSV or optionally other individual modules. You can create desktop shortcuts and associate JSV inputfiles with the jsv.bat so that double clicking a *.jsv or *.SDF file automatically starts JSV.
Performance : Java is an interpreted language and therefore slower than native code. You need at least a 166 MHz CPU, I guess. I use a 266MHz & 300MHz Pentium II computer , and I am satisfied with the performance. Of course that depends on the number of atoms,bonds and polyhedra that you display. If rotations are too slow you should switch the bonds and polyhedra off while rotating or use the economy mode.
Restrictions : JSV1.07 only allows tetrahedral or octahedral coordination polyhedra. The maximum number of atoms and bonds is set to 5000.