Understanding Bulk Electrostatic Potential in VASP
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m.fadl
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Understanding Bulk Electrostatic Potential in VASP
Hello, I want to utilize VASP for computing the band alignment. I'm using the average electrostatic potential as a reference; however, for the bulk system, the average is zero. I suspect the potential is shifted. Are there any methods to compute the potential average for the bulk? Additionally, I have another question: there are two approaches - interface with vacuum and superlattice - both widely used for this type of calculation. Should I expect to obtain the same results using both techniques?
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fabien_tran1
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Re: Understanding Bulk Electrostatic Potential in VASP
Hi,
Indeed, the average electrostatic potential (that means the Fourier coefficient corresponding to G=0) is set to zero. Anyway, the value of the average potential in the bulk is itself not important. What matter and have a physical meaning are differences, e.g., the difference between the average electrostatic potential and the Fermi energy. I have moved your post to "From Users for Users" such that other users may help you regarding your second question.
Indeed, the average electrostatic potential (that means the Fourier coefficient corresponding to G=0) is set to zero. Anyway, the value of the average potential in the bulk is itself not important. What matter and have a physical meaning are differences, e.g., the difference between the average electrostatic potential and the Fermi energy. I have moved your post to "From Users for Users" such that other users may help you regarding your second question.