Electronic structure codes create cube files to represent 3D scalar data such as charge, potential and LDOS
properties and methods of this class
There are several challenges against using cube files as reliable outputs
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First of all the maximum value are strongly dependent on the origin of grid
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The summation of all values is also grid dependent (making denser grid can solve problem somehow)
cube.xyz mesh: This return a list containing Three 3D arrays (grids) related to the cube file in other word one can extract all these arrays by
X,Y,Z=cube1("test.cube").xyzmesh
This can be used to form a desired function of these mesh points and compare it with other data
for example we can make a function for electrostatic potential as follows:
This
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gaussian cubegen
you need an input file like this
-1 -6.512752 -6.512752 -6.512752 -83 0.168040 0.000000 0.000000 79 0.000000 0.168040 0.000000 79 0.000000 0.000000 0.168040
to create your own cube file with cubegen by following command
cubegen 1 fdensity=scf Test.FChk result.cube -1 < value.txt
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NWCHEM input to generate inputs
In the case of nwchem we can change
start n1 geometry units au noautosym noautoz nocenter C 0.0 0.0 0.0 O 2.1 0.0 0.0 end basis; * library cc-pvdz;end dft iterations 50 vectors output co.movecs print kinetic_energy xc xpbe96 cpbe96 end dplot TITLE charge vectors co.movecs LimitXYZ units au -5. 5.0 79 -5. 5.0 79 -5. 5.0 79 spin total gaussian output chargedensity2.cube end