六次甲基四碲富瓦烯二碘盐的合成、晶体结构及其某些固态物性

在两相混合溶液中电解合成了HMTTeF·I_2盐的单晶。晶体属P2_1/n空间群,独立区里有一个HMTTeF分子,离子化发生在分子中的一个碲原子孤电子对上。粉末压片常温电导率为4.1×10~(-5)Scm~(-1)。喇曼光谱测定与电导率及X射线分析结果相符。     

Stretching vibrations and structure of (HF) n (n=4–8) clusters

IR spectra of 24 structural isomers of (HF) _n (n=4–8) clusters were calculated in the framework of semiempirical theory of polyatomic molecule vibrations. Based on the results obtained and available experimental data it is proposed that (HF) _n associates comprising 3–5-membered cycles with attached monomeric HF units are present in molecular beams and gas phase.Ab initio calculations performed by the SCF method show the existence of local minima corresponding to such structures on the potential energy surface of (HF) _n clusters (n=4–6). Translated fromIzvestiya Akademii Nauk. Seriya Khimicheskaya, No. 3, pp. 435–443, March, 1997.     

环状芴基张力半导体拉曼光谱理论与实验研究

环状芴基张力半导体由于其特殊的分子结构，发射状排布的p轨道和纳米级空腔等诸多特点，引起了科学家广泛的关注.相对于直链型芴基半导体，环状芴基张力半导体展现出独特的光电性质.然而，迄今为止其振动性质没有被报道.对四元环芴的晶体与直链四聚芴粉末样品进行拉曼光谱表征和归一化处理，并结合理论计算.结果表明，与直链寡聚芴相比，环芴类似于碳纳米管的G峰发生了偏移，并且低频区域拉曼频移峰的峰强增加.其原因是由于张力的引入，改变了芴基主链的骨架和电子结构，加强芴骨架上π电子离域，同时使环芴中每个芴单元都参与到振动中.该研究结果为芴基张力半导体材料拉曼光谱的研究提供了一定的工作基础.     

云南几次中强地震热红外异常特征对比研究

云南省位于多个地块交界处，构造活动活跃且地震活动频发。利用中国静止气象卫星风云二号系列相当黑体温度TBB数据，应用小波变换和相对傅氏功率谱的时频相对功率谱方法（T-F RPS），提取并分析了云南省2008年至今发生的5.5级以上地震热红外异常信息，且对比分析了特征周期、特征幅值、异常形态、异常演化过程等参数。结果表明：（1）该系列地震热红外异常信息易于用时频相对功率谱方法（T-F RPS）提取识别，且异常特征具有"出现-扩大-减小-消失"的规律；（2）异常特征周期和持续时间也具有一定的规律性；（3）异常沿着断层延展，震中位于异常边缘一侧或者异常区域交汇地带，发震时刻多位于相对功率谱幅值下降阶段；（4）震级与相对功率谱峰值有一定的相关性，震级高，峰值也较高；（5）地震类型与异常面积有一定的相关性，双震型地震异常面积较大。此外，讨论了地震热红外异常与构造活动、气候状况、天气情况和季节等因素的关系。     

Interaction of zinc finger ZNF191(243—368) and its I323 W and R327W mutants with oligonucleotides by florescence spectrum

Two mutants of the zinc finger protein, ZNF191 (243–368) I323W and R327W, are successfully obtained by site-directed mutagenesis. The fluorescence spectrum is used to study the interaction between these two mutants and the oligonucleotides. The influence of the mutation on the interaction has been studied using ethidium bromide (EB) as the fluorescence probe. The binding constants of the I323W-DNA and R327W-DNA have been calculated and the possible binding models have been discussed.     

Theoretical prediction on vibrational spectra of [Ar...Ar-H]<Superscript>+</Superscript>

Centrosymmetric linear [Ar-H-Ar]⁺ and asymmetric linear [Ar---Ar-H]⁺ are two stable configurations of [Ar₂H]⁺. Based on the global potential energy surface of [Ar₂H]⁺ provided by our group recently, we calculated the vibrational spectra of [Ar---Ar-H]⁺ with total angular momentum J = 0 by time-dependent quantum mechanical method, and the influence of quantum tunneling effect on vibrational spectra was found. With the help of the observation on the eigenstate functions and the modified potential energy surface, assignments were made to the spectra. The strong coupling between the excited bending mode of [Ar-H-Ar]⁺ and the vibrational states of [Ar---Ar-H]⁺ was discussed.     

Computer-assisted structure elucidation of organic compounds III: Automatic fragment generation from13C-NMR spectra

The interpretation of carbon-NMR spectra is mainly based on the comparison with suitable reference data taken from literature. The whole information contents of¹³C-NMR spectra cannot be utilized by manual interpretation. Therefore a network of interactive computer programs has been developed, which simulates the strategy of the spectroscopist in generating structural fragments from the spectral data. The most important knowledge source for this process is a carbon-NMR data base containing some 17,500 spectra. Structural fragments are generated automatically from this data file and assembled by a model builder to complete chemical structures using constraints derived from the spectral data. A comparison of the experimental carbon-NMR spectrum with the estimated ones allows the generation of a sorted hitlist.For part II see: H. Kalchhauser, W. Robien,J. Chem. Inf. Comput. Sci. 1985,25, 103.     

Vibrational spectra of 2-biphenylmethanol. Spectrum simulation and molecular structure

The vibrational spectra of a solid crystalline sample of 2-biphenylmethanol have been measured at room temperature. The IR absorption spectra were recorded in the range 400 cm^–1–3600 cm^–1; Raman spectra were measured in the range 10 cm^–1–1640 cm^–1. The direct mechanical and optoelectronic problems were solved using the fragment method realized as Lev-100 software; the intensity distribution in the IR spectrum of 2-biphenylmethanol was obtained by the same method. The experimental Raman and IR absorption spectra were interpreted by analyzing the calculated data on the frequencies and forms of normal vibrations and their intensities in the IR spectra. IR absorption spectra were simulated for several models of 2-biphenylmethanol conformers that differ in the mutual orientation of fragments. Based on the results of simulation and comparison of the calculated and experimental spectra of conformers we suggested a model for the conformer realized in the solid phase under normal conditions.Original Russian Text Copyright © 2004 by L. M. Babkov, J. Baran, N. A. Davydova, J. I. Kukielskii, and S. V. TrukhachevTranslated from Zhurnal Strukturnoi Khimii, Vol. 45, No. 4, pp. 624–631, July–August, 2004.This revised version was published online in April 2005 with a corrected cover date.     

Quantum-chemical analysis of the CuCl2 molecule

This paper reports on quantum-chemical analysis of the linear structure of CuCl₂ by Hartree-Fock (HF) and density functional theory (DFT) methods and also by time-dependent HF (TD HF) and DFT (TD DFT) techniques. Using pure DFT exchange correlation functional (B3LYP) yields the best agreement with the experimental electronic spectra of CuCl₂. In this case, the odd electron is delocalized over the molecule, spin density on copper being 0.27. The ground state of the CuCl₂ molecule is ²Π_g with linear geometry.     

新型两亲性混配钌配合物的合成及其对Hg2+的选择性“肉眼”识别

采用与文献不同的路线合成了4,4′-二(p-甲基苯基)-2,2′-二联吡啶,与文献结果相比,总收率由4.0%提高至15.3%.该化合物和4,4′-二羧基-2,2′-二联吡啶组成混合配体与金属钌配位,合成了两亲性、混配型配合物cis-N,N-4,4′-二(p-甲基)苯基-2,2′-二联吡啶-N,N-4,4′-二羧基-2,2′-二联吡啶-N,N-二异硫氰钌配合物,并用IR,UV-Vis,NMR和Maldi-TOF等手段进行表征.将该两亲性混配钌配合物首次用于对Hg2+的识别中,发现此配合物对Hg2+表现出灵敏的选择性“肉眼”识别:在DMF/乙醇溶液(体积比1∶9)中加入Hg2+后,MLCT态吸收由530nm蓝移到485nm.该配合物与Hg2+以1∶1(摩尔比)结合,检测限可低至0.5×10-6mol/L.