d-Spacing The d-spacing is one of several possible forms to represent the positional information of peaks in powder pattern. Other forms are the angle 0, or 20, or Q-values. Win DIFFRAC assumes input in the form of d-spacings. They are internally converted, e.g. ITO works only with Q's 分 苏五长 有一太苏 玉 长 d-Spacing The d-spacing is one of several possible forms to represent the positional information of peaks in powder pattern. Other forms are the angle Q, or 2Q, or Q-values. Win_DIFFRAC assumes input in the form of d-spacings. They are internally converted, e.g. ITO works only with Q's