Department of Chemistry, Key Laboratory of Yangtze River Water Environment, Ministry of Education Tongji University, Shanghai, China.
Phys Chem Chem Phys. 2013 Jun 28;15(24):9823-32. doi: 10.1039/c3cp51137e.
Reactions of laser-ablated V, Nb and Ta atoms with SO2 in excess argon during condensation gave new absorptions in the M=O stretching region, which were assigned to metal sulfide oxides SMO2 and anions SMO2(-) (M = V, Nb, Ta). The metal oxide complex OV(η(2)-SO) was also identified through the V=O and the characteristic side-on coordinated S-O stretching modes. The assignments of major vibrational modes were confirmed by appropriate S(18)O2 and (34)SO2 isotopic shifts, and density functional frequency calculations. DFT calculations were employed to study the behavior of reactions of Group V bare metal atoms with SO2, and a representative profile was derived which not only showed the preferred coordinating fashion of metal atoms but also tracked the path of S-O bond activation. The η(2)-O,O' bridge coordinated complexes are preferred with energy decreases of ca. 50 kcal mol(-1) for all three metals, which facilitate the activation of two S-O bonds in succession and finally direct the reaction to the most stable molecules SMO2 (M = V, Nb, Ta) along the potential energy surface (PES). Finally the SMO2 molecules capture electrons to give anions SMO2(-) with about 3.6 eV electron affinities based on DFT calculations.
激光烧蚀的 V、Nb 和 Ta 原子与过量氩气中的 SO2 在冷凝过程中发生反应，在 M=O 伸缩区域产生了新的吸收，这些吸收被归因于金属硫化物氧化物 SMO2 和阴离子 SMO2(-)（M = V、Nb、Ta）。通过 V=O 和特征的侧配位 S-O 伸缩模式，还鉴定了金属氧化物配合物 OV(η(2)-SO)。主要振动模式的分配通过适当的 S(18)O2 和(34)SO2 同位素位移和密度泛函频率计算得到了证实。DFT 计算被用于研究第五主族裸露金属原子与 SO2 的反应行为，并推导出了一个代表性的轮廓，该轮廓不仅显示了金属原子的优先配位方式，还跟踪了 S-O 键活化的路径。η(2)-O,O'桥配位配合物是首选的，对于所有三种金属，能量降低约 50 kcal mol(-1)，这有利于相继活化两个 S-O 键，并最终沿着势能面（PES）将反应导向最稳定的 SMO2（M = V、Nb、Ta）分子。最后，根据 DFT 计算，SMO2 分子捕获电子形成阴离子 SMO2(-)，其电子亲和力约为 3.6 eV。
