Abstract

The metacarboxyphenyl ammonium dihydrogenomonophosphate (C₇H₄NH₃OOH) H₂PO₄ was synthesized and studied by a combination of single-crystal X-ray diffraction analysis, infrared, Raman vibrational spectroscopy, and density functional computation (DFT) calculation. This compound crystallizes in the monoclinic system, with the central space group P2₁/c. Its unit-cell dimensions are a = 12.9361 (7) (Å), b = 11.7735 (6) (Å), c = 6.5764 (4) (Å), β = 102.668° (2), and V = 977.22 (9) ų.The structure determined gives a clear description of the hydrogen bonds connecting the hydrogen phosphate H₂PO₄^– with the organic matrix. The atomic arrangement of this compound is built up by symmetric (H₄P₂O₈)^2– dimers anions formed by two (H₂PO₄)^– via hydrogen bonding O1—H…O3. Each (H₂PO₄)^– aggregates with cation through hydrogen bond interactions of O–H…O(P) and N–H…O(P) types. The bands observed in the infrared and Raman spectra of (C₇H₄NH₃OOH) H₂PO₄ are assigned based on the results obtained in the literature and based on the computational group analyses performed in the factor group C_2h. Besides, the optimal molecular geometry, harmonic vibration frequencies, infrared intensities, and Raman scattering activities were calculated using the DFT approach performed with the Gaussian 09 program using the hybrid function B3LYP combining the three Becke parameters and the Lee-Yang-Parr exchange-correlation function using the 6-311 + G(d,p) base set. The highest occupied molecular orbital–lowest unoccupied molecular orbital properties and geometries of this compound were determined and discussed. The results of the calculated structural parameters are generally in agreement with the experimental investigations. The computational infrared and Raman spectra of the reference compound have been constructed.

摘要

采用单晶X射线衍射分析、红外、拉曼振动光谱和密度泛函计算(DFT)计算相结合的方法合成和研究了间羧苯基二氢一磷酸铵(C ₇ H ₄ NH ₃ OOH) H ₂ PO _{4 。}该化合物在单斜晶系中结晶，中心空间群为 P2 ₁ /c。其晶胞尺寸为a  = 12.9361 (7) (Å)、b  = 11.7735 (6) (Å)、c  = 6.5764 (4) (Å)、β = 102.668° (2) 和V  = 977.22 (9 ) Å ³_{. 确定的结构清楚地描述了连接磷酸氢盐 H 2} PO ₄ ^-与有机基质的氢键。该化合物的原子排列是由对称的 (H ₄ P ₂ O ₈ ) ^{2 –二聚体}阴离子通过氢键 O1-H…O3形成的两个 (H ₂ PO ₄ ) 。每个 (H ₂ PO ₄ ) ^–通过 O–H…O(P) 和 N–H…O(P) 类型的氢键相互作用与阳离子聚集。_{(C 7} H ₄ NH ₃的红外光谱和拉曼光谱中观察到的谱带OOH) H ₂ PO ₄根据文献中获得的结果和在因子组 C _{2h中执行的计算组分析分配}. 此外，使用结合三个 Becke 参数和 Lee-Yang-Parr 交换相关的混合函数 B3LYP 使用 Gaussian 09 程序执行的 DFT 方法计算最佳分子几何形状、谐波振动频率、红外强度和拉曼散射活动使用 6-311 + G(d,p) 基组的函数。确定并讨论了该化合物的最高占据分子轨道 - 最低未占据分子轨道特性和几何形状。计算结构参数的结果与实验研究基本一致。已经构建了参考化合物的计算红外和拉曼光谱。