Synthesis of Cubic Gauche Nitrogen (cg-N) under High Pressure and High Temperature
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摘要: 以共价N─N单键结合的三维网状聚合氮(cg-N)是一种理想的高能量密度材料。在室温下将分子态氮加压至135.6GPa,观测到了氮的一系列“固体分子态-固体分子态”转变(β-δ-ε-ζ-η);且在不引入任何激光吸收材料的情况下,直接对红色的非晶η氮进行双面金刚石压砧激光加热,在133.9GPa、2000K的条件下成功地合成出透明cg-N,并测量得到cg-N在134GPa附近拉曼A模频率对压力的变化率为1.56cm-1/GPa。
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关键词:
- 聚合氮 /
- 高能量密度材料(HEDM) /
- 高温高压 /
- 拉曼散射 /
- 激光加热金刚石压砧
Abstract: Three-dimensional polymetric cubic gauche nitrogen (cg-N) combined with covalent N─N single bonds is an ideal high energy density material (HEDM).A series of solid molecular state-to-solid molecular state transitions (β-δ-ε-ζ-η) in nitrogen were observed in experiment upon pressurizing the molecular nitrogen up to 135.6GPa in ambient condition.Under 133.9GPa and at 2000K, the transparent cg-N was successfully synthesized using the double-side laser heating diamond-anvil cell (LHDAC) without any laser absorbing material.In addition, the pressure coefficient of the Raman A mode for cg-N is 1.56cm-1/GPa at about 134GPa. -
图 3 (a) 不同压力下以及激光加热前、后氮的拉曼光谱; (b)第一次激光加热(134.3GPa、约1000K)后样品的光学照片; (c)第二次激光加热(133.9GPa、约2000K)后样品的光学照片; (d)cg-N拉曼A模频率与压力的关系,作为比较,先前报道过的理论与实验值也一同给出
Figure 3. (a)Raman spectra of nitrogen under various pressures and after LHDAC experiments; (b)Optical photograph of nitrogen after the 1st LHDAC experiment (134.3GPa and about 1000K); (c)Optical photograph of nitrogen after the 2nd LHDAC experiment (133.9GPa and about 2000K); (d)Comparison of the relation between Raman shift of A mode of cg-N and applied pressure
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