[Pw_forum] different result from vc-relax and manually scanning alat constant for crystal structure optimization

[zafar rasheed]

Dear Zhang
ofcource the Espresso will give different result as ur input file is not correct.

when you change celldm(1)......==> It means you are changing lattice constant a. So at the same time you should also change celldm(3)= your changed lattice constant divided by actual c. In this way you will get lattice constant a.

and again by chaging c and fixing a (only your celldm(3) will change ) you will get lattice constant c.

Hope you will understand.



Muhammad Zafar

PhD Scholar

Department of Physics

The Islamia University of Bahawalpur,Pakistan
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