论文标题
高压C-N化合物的新型超雄性结构
Novel superhard structures of high-pressure C-N compounds
论文作者
论文摘要
通过机器学习力场加速的结构搜索与第一原理计算相结合，我们研究了具有不同化学计量比的新的C-N化合物的结构，发现了十二个新的Superhard C-N化合物，这些结构的能量与C-C3N4相似，与C-C3N4相似，这可能是由高压实验和XR-3（C4）pa-3（C4）c4（C4）（C4）（C4）（C4）合成的。 C2/M（C2N）与先前的实验数据一致，可以用作结构候选者。根据宏硬度模型，它们都是超级结构，甚至在40GPA上的Vickers硬度，甚至Pa-3（C4N）的硬度高达82.2GPA，而PA-3（C4N）结合了高抗张和剪力电阻。与宏硬度模型和键电阻模型计算的硬度相比，我们获得了两个模型下C-N化合物的硬度和化学浓度之间的关系，除此之外，我们还计算了这些结构的断裂韧性。根据NIU的模型，P2_1/C（C4N）具有最佳的断裂韧性，在计算中高于WC，这也表明了新型C-N化合物的出色机械性能。此外，对于富含氮的结构，它们有可能用作高能量密度，PA-3（CN3），P-3C1（CN4）和I-42D（CN4）的能量密度7.076KJ/G，在7.742kJ/g和8.042kJ/g和8.045kJ/g，因此，在Cl-2的范围内，Cl-20的高度是CL-20的范围。理想地是超级材料和高能量密度材料（HEDM）。
Through machine learning force field accelerated structure search combined with first-principles calculations, we have studied the structures of new C-N compounds with different stoichiometric ratios, and found twelve new superhard C-N compounds, the energies of these structures are similar to c-C3N4 , which is possibly synthesized by high pressure experiment, the XRD of Pa-3(C4N) P3(C4N) and C2/m(C2N) are consistent with previous experimental data and can be used as the structural candidate. According to the macro hardness model, they are all superhard structures, with Vickers hardness over 40GPa, even, the hardness of Pa-3 (C4N) as high as 82.2GPa, and Pa-3 (C4N) combines high tensile and shear resistance. Compared with the hardness calculated by macro hardness model and bond resistance model, we obtained the relationship between the hardness and chemical concentration of C-N compounds under the two models, besides that, we also calculated the fracture toughness of these structures. According to Niu's model, P2_1/c(C4N) has the best fracture toughness, which is higher than WC in calculation, This also indicated the superior mechanical properties of the novel C-N compounds. Moreover, for nitrogen-rich structures, they have the potential to be used as high energy density, the energy density of Pa-3(CN3), P-3c1 (CN4), and I-42d (CN4) are 7.076kJ/g, 7.742kJ/g and 8.045kJ/g, which is close or higher than CL-20, therefore, the C-N compounds synthesized under high pressure have great potential as ideally superhard materials and high energy density materials(HEDMs).
