The Mechanism of Structure Phase Transition of Hydrogen Bonding Materials by High Pressure X-Ray Diffraction

(a)K_3D（SO_4）_2的高压X射线衍射和晶体结构在实验的基础上研制了一种单晶X射线衍射金刚石压砧式压力室。本文对K_3D（SO_4）_2单晶在高压下进行了精确的X射线结构分析。在室温高压条件下，我们收集了30%倒易晶格空间的积分强度。以下结果是明确的。(1)当压力低于3GPa时，K_3D（SO_4）_2晶体的晶体结构没有发生剧烈变化。(2)氢键长度随压力的变化而收缩。但是，这些结果与D原子的电子密度分布有较大的误差。目前，我们计划在SOR（SPring-8）中用高能X射线对K_3D（SO_4）_2单晶进行高压结构分析。(b)C_nH_<2n+1>NH_3H_2PO_4晶体的奇偶效应与晶体结构 ...更多信息 磷酸二氢钙C_nH_<2n+1>NH_3H_2PO_4（简称CnADP）晶体的单晶结构，在室温下对CnADP（n=2-6）单晶进行了X射线晶体结构分析。以下结果已明确。(1)CnADP（n=2-6）晶体属单斜晶系，空间群为P2_1/n（Z=8）。(2)CnADP（n=2-6）晶体的晶体结构特征是由反平行的平面有机链沿着b轴排列，与无机单元相互分布。(3)正烷基的重叠随着碳原子的增加而增加。认为正烷基中的末端碳原子与另一个正烷基铵基团中的氮原子之间的长度保持恒定。(4)在CnADP（n= 2，4，6）晶体中，正烷基的碳原子数为偶数，正烷基的锯齿形结构平行重叠，相互填充。另一方面，在CnADP（n=3和5）晶体的情况下，其为正烷基中的奇数个碳原子，正烷基的Z形结构重叠，就像碰撞一样。这一差异是奇偶效应的根源。少

(a) High Pressure X-Ray Diffraction and Crystal Structure of K_3D (SO_4)_2A diamond-anvil pressure cell for x-ray diffraction of single crystals was made on an experimental basis. The precise X-ray structure analysis of K_3D (SO_4)_2 single crystal under high pressure were tried. We collected integrated intensities from the 30% of reciprocal lattice spqce at room temperature under the condition of high pressure. The following results were made clear. (1) A drastic change of the crystal structure in K_3D (SO_4)_2 crystal was not observed at pressures below about 3GPa. (2) The length of hydrogen bond was contracted as function of pressure. But, these results and the distribution of electron density of D-atom had large error. Now, we plan the structure analysis of K_3D (SO_4)_2 single crystal at high pressure with high energy X-ray in SOR (SPring-8).(b) Even and Odd Effect and Crystal Structure in C_nH_<2n+1>NH_3H_2PO_4 Crystals.In order to clarify the even and odd effect in n-alkyl ammon … More ium dihydrogen phosphate C_nH_<2n+1>NH_3H_2PO_4 (abbreviated as CnADP) crystals, we carried out the x-ray crystal structure analysis in CnADP (n=2-6) single crystals at room temperature. Yhe following results were made clear. (1) CnADP (n=2-6) crystals belong a monoclinic system with space group of P2_1/n (Z=8). (2) The crystal structure of CnADP (n=2-6) crystals are characterized by an arrangement of anti-parallel planar organic chains along b-axis interdistributed with inorganic units. (3) The overlap of n-alkyl group increase with increasing carbon atoms. It was considered that the length between the end carbon atom in the n-alkyl group and the nitrogen atom in the another n-alkyl ammonium group was kept constant. (4) In the case of CnADP (n=2,4 and 6) crystals, which was the even number of the carbon atom in n-alkyl group, the zigzag structure of the n-alkyl group was overlapped in parallel and fill the space with each other. On the other hand, in the case of CnADP (n=3 and 5) crystals, which was the odd number of the carbon atom in n-alkyl group, the zigzag structure of the n-alkyl group was overlapped just like clash. It was concluded that this difference was the origin of the even and odd effect. Less