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用ＥＳＲ方法对照研究了中国出产的五颗天然金刚石单晶．四颗人造金刚石单晶和两个化学沉积金刚石膜（ＣＶＤ）等固体材料．发现Ｉｂ型天然金刚石中有四种ａＮ各向异性的Ｎ－中心自由基和一种Ｃ－中心自由基；而ＩａＢ３型的未配对电子定域在Ｎ３型杂质中心的π＊反键轨道上；Ｉｂ型人造金刚石含有少量Ｎｉ，Ｆｅ等顺磁元素造成ＥＳＲ线增宽，仅可观察到二重或三重裂分；在不同金刚石膜中．ｃ－中心自由基的浓度可以相差很大．而低浓度的Ｎ－中心自由基的浓度相对变化较小；所观察到的Ｃ－中心自由基的两个卫星峰（ａＨ＝７．２×１０－４Ｔ）是金刚石膜中１Ｈ存在的直接证据．结果表明ＥＳＲ方法是金刚石及类金刚石材料的一种快捷而有效的表征方法．
Five natural diamond single crystals made in China were compared with the ESR method. Four synthetic diamond single crystals and two chemically deposited diamond films (CVD) and other solid materials. It is found that there are four kinds of aN anisotropic N-center radical and a C-center radical in type Ib natural diamond, while the unpaired electron of type IaB3 is localized on the π * antibonding orbit of the center of N3 type impurity ; Ib artificial diamond containing a small amount of Ni, Fe and other paramagnetic elements cause ESR line broadening, only the observed double or triple cleavage; in different diamond films. The concentration of c-center free radicals can vary greatly. While the concentration of low concentrations of N-centered free radicals changed relatively less; the observed two satellite peaks of C-centered free radicals (aH = 7.2 × 10 -4 T) were direct evidence of the presence of 1H in diamond films . The results show that the ESR method is a fast and effective method for characterization of diamond and diamond-like materials.