5CLARK C D , COLLINS A T , WOODS G S, Absorption and luminescence spectroscopy [M]. The Properties of Natural and Synthetic Diamond, London: Academic Press, 1992: 35-79.
6EVANS Trevor . Aggregation of nitrogen in diamond[M]. The Properties of Natural and Synthetic Diamond, London Academic Press, 1992:259 -290.
7KIFLAWI I. MAYER A E , SPEAR P M , et al. Infrared ab- sorption by the single nitrogen and A defect centers in diamond [J]. Philosophical Magazine Part B, 1994, 9(6) : 1141-1147.
8BOYD S R , KIFLAWI I , WOODS G S. Infrared absorption by the B nitrogen aggregate in diamond [J]. Philosophical Magazine Part B, 1995, 72(3):351-361.
9CHRENKO R M , TUFT R E , STRONG H M . Transforma- tion of the state of nitrogen in diamond [J]. Nature, I977, 270 (10): 141 144.
10COLLINS A T , KANDA H , KITAWAKO H . Color changes produced in natural brown diamonds by high pressure, high-tern perature treatment [J]. Diamond and Related Materials, 2000, 9 (2): 113-122.
