[Pw_forum] Bond property analysis through Born effective charges calculation

[Lily Anh]

Dear all,

I am doing a high pressure study on CaO and I want to investigate the bond property under compression. The Born effective tensor of cubic CaO has only one independent component. The Born effective charge for Ca are larger than the nominal ionic charge +2 and increase with pressure. Does this mean the bond become more ionic or more covalent?  Since the it increase with pressure, can we say that more charge transfer from Ca to O in this case?
Any reply will be appreciated.
Thanks and regards.
Lily


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