Cho Han-Gook, Andrews Lester
Department of Chemistry , Incheon National University , 119 Academy-ro , Yeonsu-gu, Incheon 22012 , South Korea.
Department of Chemistry , University of Virginia , P.O. Box 400319, Charlottesville , Virginia 22904-4319 , United States.
J Phys Chem A. 2019 Jul 25;123(29):6259-6268. doi: 10.1021/acs.jpca.9b04177. Epub 2019 Jul 10.
Tin insertion products (oxidation state 2+) were observed in reactions of laser-ablated Sn atoms with ethane, and halomethanes in excess argon, parallel to the Pb reactions. The CSnX bond angles of the observed Sn complexes are close to right angles, and natural bond orbital calculations show that Sn also utilizes mostly its p-orbitals to make chemical bonds. Bridged Sn complexes [CX(X)-SnX] were also provided in reactions of tetrahalomethanes via photo-isomerization of the insertion products, showing that the p-orbitals of Sn are more accessible than those of Pb. These products were identified from the matrix infrared spectra on the basis of isotopic shifts and density functional theory frequencies. Considering the previously reported high-oxidation-state products of the lighter group 14 elements and the Pb products with primarily oxidation state 2+ because of the relativistic effects, the observed Sn complexes show a trend that the high-oxidation-state complexes are less favored with increasing atomic mass in group 14, which is opposite to that observed in transition-metal columns.
在激光烧蚀的锡原子与乙烷以及过量氩气中的卤代甲烷的反应中，观察到了锡插入产物（氧化态为2+），这与铅的反应情况类似。所观察到的锡配合物的CSnX键角接近直角，自然键轨道计算表明，锡也主要利用其p轨道来形成化学键。通过插入产物的光异构化，在四卤代甲烷的反应中还生成了桥连锡配合物[CX(X)-SnX]，这表明锡的p轨道比铅的p轨道更容易参与反应。这些产物是根据同位素位移和密度泛函理论频率，从基质红外光谱中鉴定出来的。考虑到先前报道的较轻第14族元素的高氧化态产物以及由于相对论效应主要为氧化态2+的铅产物，所观察到的锡配合物显示出一种趋势，即随着第14族原子质量的增加，高氧化态配合物越来越不受青睐，这与在过渡金属列中观察到的情况相反。
