a ejima crystal bụ a crystal nke a na-esịnede abụọ halves nke otu crystal ma ọ bụ abụọ ma ọ bụ karịa kristal nke otu umu nke nwere kpọmkwem crystallographic mmekọrịta ibe na emewo ọnụ a symmetrical n'ụzọ (lee kọntaktị ejima na interpenetrant ejima)
