抄録
The concept of the second-nearest-neighbor electron (SNE) interaction has been introduced recently to explain the piezoelectric constants and Szigeti effective charges. But the idea of SNE interaction is criticized because of the lack of warrant for actual existence of it. This paper gives the relative strength of the SNE interaction energy in diamond using the LCAO band theory of J. C. Slater. The SNE interaction energy is 42% of the ordinary chemical bond energy in diamond.
