some question about MD calculations

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tfb · #1 Post by **tfb** » Tue Oct 30, 2007 12:16 pm

I just begin to learn do MD calculations,and feel puzzled about some following questions, if anyone can help me ?
first when I do MD calculations,after the system is in
equilibrium ,I found the E total is little than E0,something like this T= 713. E= -.24943116E+03 F= -.24560357E+03 E0= -.24559125E+03 EK= 0.11706E+02 SP= -.16E+02 SK= 0.75E-01
Is it a normal behavior ?
another question is when do MD calculation ,how to calculation DOS, charge density diagram, is it the same ordianary DOS charge and density diagram calculation?
I have seen the vasp guide ,and know how to calculate those in ordinary way, but how it is applied to MD culcalations .
thank you in advance,any help will be appreciated.

#2 Post by **admin** » Tue Nov 06, 2007 1:30 pm

TOTEN is the free energy, containing the electronic entropy contribution, therefore it has to be slightly smaller that E0
sorry, I don't understand your second question, but maybe this is an answer: DOSCAR and CHGCAR are always written at the end of a vasp run (not matter whether you do MD or not)

tfb · #3 Post by **tfb** » Sat Nov 10, 2007 1:04 pm

I want to calculate the PDOS ,total DOS and charge density diagram during the MD calculations ,so how to set the parameters in the INCAR file ,and what I must take care of ?
thank you very much.

#4 Post by **admin** » Mon Nov 12, 2007 11:28 am

1) to obtain the PDOS, please choose LORBIT appropriately.

2) DOSCAR and CHGCAR are written by default at the end of a vasp-run. If you want to have it written more often, please choose KBLOCK and NBLOCK accordingly. Please don't forget to modify your job script such that DOSCAR and CHGCAR are not overwritten.

fanghz · #5 Post by **fanghz** » Wed Dec 19, 2007 12:59 am

By the way, can you explain the differences between E, F and E0 in more detail ? I'm also puzzled by this problem, thank you a lot !