水热法合成了一个无机-有机杂化的NH_(4)[Cu_(3)^(I)(C_(10)H_(8)N_(2))_(3)Mo_(8)O_(26)]化合物,通过元素分析和单晶X-射线衍射进行了表征。化合物为三斜晶系,P1空间群,晶胞参数a=1.08763(9)nm,b=1.12674(10)nm,c=1.13067(10)nm,α=68....水热法合成了一个无机-有机杂化的NH_(4)[Cu_(3)^(I)(C_(10)H_(8)N_(2))_(3)Mo_(8)O_(26)]化合物,通过元素分析和单晶X-射线衍射进行了表征。化合物为三斜晶系,P1空间群,晶胞参数a=1.08763(9)nm,b=1.12674(10)nm,c=1.13067(10)nm,α=68.4820(10)°,β=83.523(2)°,γ=64.4180(10)°,V=1.16095(2)nm^(3),Z=1,Dc=2.661 g/cm^(3),Mr=1860.73,μ(MoKα)=35.22 cm^(-1),F(000)=888,R=0.0478,wR=0.099。化合物的结构包含2个结晶学上独立的铜原子、不连续的多氧阴离子β-[Mo_(8)O_(2)6]4-和无限扩展的[Cu I(C_(10)H_(8)N_(2))]链。每一个铜原子为类似的{CuN_(2)}配位模式,被4,4’-联吡啶连接成一维沿a轴方向的[Cu(C 10 H 8 N 2)]+链。分子结构中存在氢键和π…π作用。对化合物的热稳定性、荧光性质也进行了研究。展开更多
本文研究了[NH_3Pr^t]_6[Mo_8O_(28)(CHO)_2]·2H_2O单晶在紫外光辐照后的电子顺磁共振波谱.观察到三组包含质子超精细结构的 EPR 谱线.线组Ⅰ和Ⅱ分别归属于正文中局部八面体顺磁中心A 和 B,而线组Ⅲ则可能归属于一种不稳定的顺磁...本文研究了[NH_3Pr^t]_6[Mo_8O_(28)(CHO)_2]·2H_2O单晶在紫外光辐照后的电子顺磁共振波谱.观察到三组包含质子超精细结构的 EPR 谱线.线组Ⅰ和Ⅱ分别归属于正文中局部八面体顺磁中心A 和 B,而线组Ⅲ则可能归属于一种不稳定的顺磁中心.从 EPR 数据使用最小二乘拟合技术得到了精确的各向异性 g 张量主值、A 张量主值,以及它们的主轴相对于实验坐标的方向余弦.由 A值估算了电子自旋密度.结果表明 Mo 未成对电子主要处于 Mo 的 d 轨道,并与 H 原子轨道发生直接偶合作用.展开更多
Two possible structures of Mo 8O 4- 26 were optimized using the Polak-Ribiere method of Molecular Mechanics Optimization and the termination condition is RMS (Root-mean-square) gradient of 0.42 kJ/mol. Based on the ca...Two possible structures of Mo 8O 4- 26 were optimized using the Polak-Ribiere method of Molecular Mechanics Optimization and the termination condition is RMS (Root-mean-square) gradient of 0.42 kJ/mol. Based on the calculations of the molecular dynamics, Lengevin dynamics and Monte Carlo dynamics simulation, the structure models of Mo 8O 4- 26 with the lowest energy were acquired respectively according to the energy of the systems calculated using the ZIDO/1 and PM3 methods. The total energy, energies of some frontier molecular orbitals and atomic charges of Mo 8O 4- 26 were computed at the HF/3-21G and HF/STO-3G levels. The calculation results show that the contortion of the structure with eight MoO 6 is smaller than that of the structure with six MoO 6 and two MoO 4. The total energies of the two structures are nearly equal because the contortion of the structure with six MoO 6 and two MoO 4 would make the exclusion force decreased.展开更多
The precursor ZrW1.6Mo0.4O7(OH)2(H2O)2 was characterized by IR and XRD methods. δ′-ZrW1.6Mo0.4O8 was prepared by careful controlling the annealing conditions from the precursor and was determined to have the formula...The precursor ZrW1.6Mo0.4O7(OH)2(H2O)2 was characterized by IR and XRD methods. δ′-ZrW1.6Mo0.4O8 was prepared by careful controlling the annealing conditions from the precursor and was determined to have the formula as o-ZrW1.6Mo0.4O8·H2O by TG-DSC, IR, and XRD methods. The relation between o-ZrW1.6Mo0.4O8·H2O and o-ZrW1.6Mo0.4O8 was discussed through variable temperature XRD patterns. Further more, the mechanism of the precursor dehydration was suggested.展开更多
文摘水热法合成了一个无机-有机杂化的NH_(4)[Cu_(3)^(I)(C_(10)H_(8)N_(2))_(3)Mo_(8)O_(26)]化合物,通过元素分析和单晶X-射线衍射进行了表征。化合物为三斜晶系,P1空间群,晶胞参数a=1.08763(9)nm,b=1.12674(10)nm,c=1.13067(10)nm,α=68.4820(10)°,β=83.523(2)°,γ=64.4180(10)°,V=1.16095(2)nm^(3),Z=1,Dc=2.661 g/cm^(3),Mr=1860.73,μ(MoKα)=35.22 cm^(-1),F(000)=888,R=0.0478,wR=0.099。化合物的结构包含2个结晶学上独立的铜原子、不连续的多氧阴离子β-[Mo_(8)O_(2)6]4-和无限扩展的[Cu I(C_(10)H_(8)N_(2))]链。每一个铜原子为类似的{CuN_(2)}配位模式,被4,4’-联吡啶连接成一维沿a轴方向的[Cu(C 10 H 8 N 2)]+链。分子结构中存在氢键和π…π作用。对化合物的热稳定性、荧光性质也进行了研究。
文摘本文研究了[NH_3Pr^t]_6[Mo_8O_(28)(CHO)_2]·2H_2O单晶在紫外光辐照后的电子顺磁共振波谱.观察到三组包含质子超精细结构的 EPR 谱线.线组Ⅰ和Ⅱ分别归属于正文中局部八面体顺磁中心A 和 B,而线组Ⅲ则可能归属于一种不稳定的顺磁中心.从 EPR 数据使用最小二乘拟合技术得到了精确的各向异性 g 张量主值、A 张量主值,以及它们的主轴相对于实验坐标的方向余弦.由 A值估算了电子自旋密度.结果表明 Mo 未成对电子主要处于 Mo 的 d 轨道,并与 H 原子轨道发生直接偶合作用.
文摘Two possible structures of Mo 8O 4- 26 were optimized using the Polak-Ribiere method of Molecular Mechanics Optimization and the termination condition is RMS (Root-mean-square) gradient of 0.42 kJ/mol. Based on the calculations of the molecular dynamics, Lengevin dynamics and Monte Carlo dynamics simulation, the structure models of Mo 8O 4- 26 with the lowest energy were acquired respectively according to the energy of the systems calculated using the ZIDO/1 and PM3 methods. The total energy, energies of some frontier molecular orbitals and atomic charges of Mo 8O 4- 26 were computed at the HF/3-21G and HF/STO-3G levels. The calculation results show that the contortion of the structure with eight MoO 6 is smaller than that of the structure with six MoO 6 and two MoO 4. The total energies of the two structures are nearly equal because the contortion of the structure with six MoO 6 and two MoO 4 would make the exclusion force decreased.
文摘The precursor ZrW1.6Mo0.4O7(OH)2(H2O)2 was characterized by IR and XRD methods. δ′-ZrW1.6Mo0.4O8 was prepared by careful controlling the annealing conditions from the precursor and was determined to have the formula as o-ZrW1.6Mo0.4O8·H2O by TG-DSC, IR, and XRD methods. The relation between o-ZrW1.6Mo0.4O8·H2O and o-ZrW1.6Mo0.4O8 was discussed through variable temperature XRD patterns. Further more, the mechanism of the precursor dehydration was suggested.
