Co,Fe,Mn,Cr,Mo,Ag 2dsin0=nλ d=nλ/2sin0 d≥λ/2 d=a/(h2+k2+l2)1/2Co,Fe,Mn,Cr,Mo,Ag 2dsinθ=nλ d=𝑛λ/2sinθ d≥λ/2 d=a/(h2+k2+l2 ) 1/2