Department of Chemistry, University of Georgia, Athens, Georgia 30602, USA.
J Phys Chem A. 2012 Feb 9;116(5):1375-82. doi: 10.1021/jp211578t. Epub 2012 Feb 1.
Si(CO)(n)(+) and Si(CO)(n)(+)Ar complexes are produced via laser vaporization with a pulsed nozzle source and cooled in a supersonic beam. The ions are mass selected in a reflectron time-of-flight mass spectrometer and studied with infrared laser photodissociation spectroscopy near the free molecular CO vibration (2143 cm(-1)). Si(CO)(n)(+) complexes larger than n = 2 fragment by the loss of CO, whereas Si(CO)(n)(+)Ar complexes fragment by the loss of argon. All clusters have resonances near the free molecular CO stretch that provide distinctive patterns from which information on their structure and bonding can be obtained. The number of infrared-active bands, their frequency positions, and relative intensities indicate that larger species consist of an asymmetrically coordinated Si(CO)(2)(+) core with additional CO ligands attached via van der Waals interactions. Density functional theory computations are carried out in support of the experimental spectra.
Si(CO)(n)(+) 和 Si(CO)(n)(+)Ar 配合物通过激光蒸发带有脉冲喷嘴的源产生，并在超音速射流中冷却。离子在反射飞行时间质谱仪中进行质量选择，并在自由分子 CO 振动（2143 cm(-1)）附近用红外激光光解光谱进行研究。Si(CO)(n)(+) 配合物大于 n = 2 通过 CO 的损失而片段化，而 Si(CO)(n)(+)Ar 配合物则通过氩的损失而片段化。所有团簇在自由分子 CO 伸展附近都有共振，这些共振提供了独特的图案，从中可以获得有关其结构和键合的信息。红外活性带的数量、它们的频率位置和相对强度表明，较大的物种由一个不对称配位的 Si(CO)(2)(+)核心组成，通过范德华相互作用附加额外的 CO 配体。密度泛函理论计算为实验光谱提供支持。
