硅硫二元团簇[(SiS2)nSiS]+(n=1～3)的结构和稳定性的量子化学研究

用密度泛函(DFT)方法(B3LYP/6-31G*)研究了硅硫团簇[(SiS2)nSiS]+(n=1～3)的可能几何构型,得到各稳定构型的电子结构,并计算了相应的振动频率,预测了稳定构型的振动光谱.由其稳定构型的比较可在理论上预测团簇的生长规律,并可初步预测团簇的形成机理.     

硅-硫团簇(SiS2)+n(n=1-3)的结构和振动光谱的量子化学研究

用密度泛函（ＤＦＴ）方法研究了硅硫团簇（ＳiＳ２）n＋（n＝１－３）的各种可能的几 何构型和电子结构,并计算了相应的振动光谱,得到（ＳiＳ２）n＋的生长规律,由此预测了（ＳiＳ２）n＋团簇的形成机理。     

紫外光激励产生高振动激发ν_1模的NO_2分子

NO2的光解研究不仅在大气化学等领域有着重要意义，而且在单分子解离模型的建立等分子反应动力学理论研究上也有着重要的价值．因此，它一直被不同的实验方法进行着深入的研究．NO2的解离极限波长是398nm．由干室温下NO2振、转动能的能量贡献，在长干解高限的404．7。仍有多达3     

C2H3自由基与O2反应的红外发射光谱及反应通道

The reaction of vinyl radicals with oxygen was investigated by Time-Resolved Fourier Transform infrared emission spectroscopy. The radicals were produced by the pulsed laser photolysis of C_2H_3Br at 248 nm. Vibrationally excited products of H_2CO(v1), HCO(v3), CO_2(v3, v), CH_3(v3), C_2H_2(v3), HO_2(v1), C_2H_2O_2(v3+v11), CO(v) formed in the C2H3+O_2 reaction have been observed. Four elementary reaction channels have been verified.     

O(1D)+Si(CH3)3Cl反应生成振动激发的OH(ν≤3)

The vibrationally excited OH(v) from the reaction of O(~1D)+Si(CH_3)_3Cl was observed by UV laser photolysis/FTIR emission spectroscopy. The vibrational number was only up to 3 with a ratio of 1:0.8:0.1 for v=1:2:3. Comparing this result with the similar reaction of O(~1D)+Si(CH_3)_4 which OH(v) vibrational number was high up to 4 with a ratio of 1:1:1:0.3 for v=1:2:3:4 under the same experimental conditions, it was found that the substitution of Cl for CH_3 affected the extent of heavy Si atom blocking the energy migration in a molecule. This results identifies the prediction that the characteristic of electrons in central atom plays an important role in intramolecular energy transfer.     

钪-硫团簇的形成和光解

报道了用激光直接溅射法产生钪硫团簇, 并用串级飞行时间质谱仪研究了所产生的团簇离子的分布及紫外激光光解规律。钪硫二元团簇正负离子都是由周边硫原子包围团簇骨架而构成的, 骨架是由包含着不同数目的Sc2S3这样的组份单元组成, 它们结合紧密, 构成了稳定的钒硫团簇的核心。稳定的团簇正离子为ScS(Sc2S3)n^+和Sc2S2(Sc2S3)n^+。稳定的团簇负离子为ScS2(Sc2S3)n^-,S3(Sc2S3)n^-, (Sc2S3)n^-。周边硫原子数目随样品中硫的摩尔含量的增加而增多, 它们结合较弱, 易于剥离。在紫外光解时往往以失去S2, S4, S6的方式解离。通过分析认为具有组份单元的Sc对于S团簇的结构可能是一种笼状结构。     

CH2+O2反应的反应机理

The mechanisms of the CH2＋ O2→ H2O＋ CO and CH2＋ O2→ H2＋ CO2 reactions have been studied by performing ab initio CAS(8,8)/6-31G(d,p) calculations, and five intermediates(IMn) and eight transitions(TSn) have been located along the reaction paths. The predicted path for the CH2＋ O2→ H2O＋ CO is: CH2＋ O2→ TS1→ IM1→ TS2→ IM2→ TS3→ IM3→ TS4→ IM4a→ TS5→ H2O＋ CO. For the CH2＋ O2→ H2＋ CO2 reaction, there are two paths: (i) CH2＋ O2→ TS1→ IM1→ TS2→ IM2→ TS3→ IM3→ TS6→ H2＋ CO2 and (ii) CH2＋ O2→ TS1→ IM1→ TS2→ IM2→ TS3→ IM3→ TS4→ IM4a→ TS7→ IM4b→ TS8→ H2＋ CO2, with the latter path more favorable energetically.     

Formation of binary silver sulfide clusters and sulfur sensitization of photographic process

Formation of silver sulfide binary cluster ions,as well as the effects of silver and sulfur content proportion,the cluster size range,the influence of laser fluence,the UV laser photolysis,etc.,was studied with the laser ablation method and a tandem time-of-flight mass spectrometer.The results show that there exist two different forms of positively charge-bearing cluster ions;[(Ag2S)n Ag] + and [ (Ag2S)n-1 Ag3]+.The most possible forms of the sulfur sensitization centers acting as traps of photoelectrons are [Ag2S] +,[ Ag2S Ag] +,[ Ag2S Ag3]+ and the analogs.     

激光对火焰的诊断Ⅲ. 激光诱导荧光法对液化石油气/空气火焰中的C2和CH基浓度分布的检测

通过对部份预混的富燃料液化石油气/空气火焰中各部份的C_2(A~(3Π)←→X~(3Π)和CH(B~(2∑)←X~(2Π), (A~(2Δ)→X~(2Π))的激光诱导荧光信号进行逐点检测, 首次获得了C_2(X)和CH(X)基在火焰中央纵剖面上的二维等浓度线分布图。它们的分布都在内焰锥形的壳层上, 而以锥顶区域最浓。C_2主要来自热解, 并可进一步聚成碳核。CH的形成是来自小自由基和含氧化合物的反应, 它进一步燃烧成终产物。     

红外多光子解离亚磷酸三甲酯产生可见及紫外荧光的研究

近年来,科学家们为了寻找一种在可见区工作的化学激光体系,重新对一些高放热的磷化物的化学发光反应发生兴趣.对磷化物光解行为的研究表明,光解过程和产物与燃烧反应有许多相似之处.这是磷化物光解方面的初步探索.十年前,Merrow 和Nogar 曾用TEA CO_2激光对亚磷酸三乙酯P(OC_2H_5)_3进行了红外