Vibrational spectroscopic properties of molybdenum and tungsten N2 and N2Hx complexes with depe coligands: comparison to dppe systems and influence of H-bridges
Vibrational spectroscopic properties of molybdenum and tungsten N2 and N2Hx complexes with depe coligands: comparison to dppe systems and influence of H-bridges
复制标题
钼和钨 N2 和 N2Hx 配合物与 depe 共配体的振动光谱性质：与 dppe 系统的比较以及 H 桥的影响
DOI：
10.1016/s0010-8545(03)00064-x
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发表时间：
2003
影响因子：
20.6
通讯作者：
N. Lehnert
中科院分区：
文献类型：
--
作者：
F. Tuczek;Kay H. Horn;N. Lehnert
用红外光谱和拉曼光谱研究了双氮配合物[M（N2）2（depe）2]（M=Mo，W）和[Mo（N2）2（depe）2]经HCl质子化后得到的NNH 2配合物[MoCl（NNH 2）（depe）2]Cl的振动结构.用量子化学辅助的简正坐标分析方法，对天然丰度N、15 N和2 H同位素取代衍生物的振动数据进行了评价，给出了这些体系的实验校准力场。这种处理的结果进行了比较与类似的dppe络合物（dppe= 1，2-双（二苯基膦基）乙烷）。[M（N2）2（diphos）2]（M=Mo，W，diphos=depe，dppe）的N → N频率和力常数表明N2的活化顺序为[W（N2）2（depe）2]>[W（N2）2（dppe）2]>[Mo（N2）2（depe）2]>[Mo（N2）2（dppe）2]. [MoCl（NNH 2）（depe）2]Cl的光谱与[WF（NNH 2）（dppe）2] BF 4的光谱有显著差异，这归因于Mo的二聚体结构，由两个Cl−阴离子桥接。得到的结果上的双氮配合物被认为是在一个更广泛的范围内的钼和钨NNHX系统与dppe和depe的共配体，和力常数的演变后，连续质子化的N2配体进行了讨论。
The vibrational structures of the dinitrogen complexes [M(N2)2(depe)2], M=Mo, W, and the NNH2complex [MoCl(NNH2)(depe)2]Cl derived from [Mo(N2)2(depe)2] by protonation with HCl are investigated with the help of infrared and Raman spectroscopy (depe=1,2-bis(diethylphosphino)ethane). Vibrational data obtained from natural abundance-N,15N and2H isotope substituted derivatives are evaluated with the quantum-chemistry assisted normal coordinate analysis procedure, giving an experimentally calibrated force field for these systems. The results of this treatment are compared with those obtained on analogous dppe complexes (dppe=1,2-bis(diphenylphosphino)ethane). The NN frequencies and force constants of the dinitrogen complexes [M(N2)2(diphos)2], M=Mo and W, diphos=depe, dppe, indicate an activation of N2in the order [W(N2)2(depe)2]>[W(N2)2(dppe)2]≈[Mo(N2)2(depe)2]>[Mo(N2)2(dppe)2]. The spectra of [MoCl(NNH2)(depe)2]Cl show significant differences with respect to those of [WF(NNH2)(dppe)2]BF4which are ascribed to a dimeric structure of the Modepe complex, being bridged by two Cl−anions. The results obtained on the dinitrogen complexes are considered within a broader range of Mo and WNNHxsystems with dppe and depe coligands, and the evolution of force constants upon successive protonation of the N2ligand are discussed.