The Characterization of synthetic and natural single crystal diamonds by X-ray diffraction

Maeta, Hiroshi*; Matsumoto, Norimasa*; Haruna, Katsuji*; Saotome, Takao*; Ono, Fumihisa*; Sugai, Hiroyuki; Otsuka, Hideo; Ohashi, Kazutoshi*

Natural and synthetic single crystal diamonds (type Ia, Ib, IIa and IIb) have been characterized by measurements of the X-ray integrated scattering intensity, lattice parameter and diffuse scattering. We found that the lattice parameter is smallest for natural diamond and largest for the B-doped diamond. We measured the diffuse scattering for (400) Bragg reflection for the four types of crystals. The scattering intensity of the natural crystals diffuses asymmetrically to form a streak along the [100] direction parallel to the reciprocal lattice vector. These results suggest the existence of the nitrogen atom platelets on (100) plane in the natural diamond. We also found the diffuse streaks along the [00] direction for (400) Bragg reflection for the B-doped crystal, suggesting that boron atoms are likely to form precipitates on the (100) plane.