新显色剂四(邻氯对磺酸基苯基)卟啉导数分光光度法同时测定镉和铅的研究

在pH 10.7,有溴化十六烷基二甲基乙酸铵存在,咪唑催化新显色剂四(邻氯对磺酸基苯基)卟啉与镉和铅反应生成三元胶束络合物,最大吸收波长分别为437和470nm,其表观摩尔吸光系数相应为5.6×10~5和2.0×10~5。用二阶导数分光光度法同时测定镉和铅,结果满意。     

天然环状四吡咯化合物的合成研究进展

天然环状四吡咯化合物包括卟啉、卟吩、细菌卟吩、异菌卟吩以及可啉等类物质 ,其合成研究是目前有机合成领域的热点之一 .综述了上述各类物质的全合成方法及其研究进展     

单质子化卟吩构型的理论研究

使用从头算Ｈａｒｔｒｅｅｅ－Ｆｏｃｋ和密度泛函Ｂ３ＬＹＰ方法计算了单质子化卟吩（ＰＨ３＾＋）的构型。用ＨＦ方法只能得到Ｃ１性的构型。当考虑相关后,用密度泛函Ｂ３ＬＹＰ方法在３－２１Ｇ,３－２１Ｇ（ｐ）,６－３１Ｇ三个基组水平得到了具有Ｃｓ的对称性的结构,推测这种结构是合理的。     

Effect of the Central Atom of a Metal on the Structure and Frequencies of the Normal Vibrations of the Porphin Ligand

The structure and frequencies of the normal vibrations of the molecules of porphin, Mg-, Zh-, and Ni-porphin were calculated by the density-functional method in the B3LYP/6-31G(d) approximation, and correlation of their frequencies was made. The force fields have been obtained in dependent natural coordinates. It is shown that the majority of changes in the vibrational frequencies in transition from porphin to its metal complexes correlate with changes in the structure of the pyrrole and pyrrolenine rings of the porphin ligand.     

Calculation of Quantum‐Chemical Characteristics of the Ground and Excited Electronic States of Porphin and Its Tetrapyrrole Isomers

Using the CNDO/S method, we have performed quantumchemical calculations of the ground and excited electronic states of porphin molecules (symmetry D _2h ) and a number of porphin isomers: porphycene (C_2h ), hemiporphycene, corphycene (C_2v ), isoporphycene, and three nonsynthesized structural isomers of the porphin skeleton by its bridge groups —(CH) _meso —. The results of the calculations are compared with the corresponding data for the freebase porphin molecule (H₂P). Near the boundary between the occupied and vacant orbitals the isomers form rows of singleelectron levels with similar energy characteristics. For the MOs of these isomers, the H₂P MOs closest in distribution on the comparable atomic centers are given. The weak (Q) and strong (B) transitions in the visible and near UV regions point to the porphyrin type of spectra of all the isomers. The calculation data on the excited electronic states of N, g, and ntype H₂P near and above the B states are given; the presence of such states in other isomers is shown. The calculation does not point to a difference in the position of the first singlet transitions in the first five isomers. The calculation data on the lower singlettriplet transitions are also reported.     

New perspectives in multireference perturbation theory: the n-electron valence state approach

The n-electron valence state perturbation theory (NEVPT) is a form of multireference perturbation theory which is based on a zero order reference wavefunction of CAS-CI type (complete active space configuration interaction) and which is characterized by the utilization of correction functions (zero order wavefunctions external to the CAS) of multireference nature, obtained through the diagonalization of a suitable two-electron model Hamiltonian (Dyall’s Hamiltonian) in some well defined determinant spaces. A review of the NEVPT approach is presented, starting from the original second order state-specific formulation, going through the quasidegenerate multi-state extension and arriving at the recent implementations of the third order in the energy and of the internally contracted configuration interaction. The chief properties of NEVPT—size consistence and absence of intruder states—are analyzed. Finally, an application concerning the calculation of the vertical spectrum of the biologically important free base porphin molecule, is presented.     

以meso-四(4-甲基-3-磺酸基苯基)卟啉荧光熄灭法连续测定环境水样中的痕量铜和锌

本文利用水溶性卟啉meso-四(4-甲基-3-磺酸基苯基)卟啉(TTPS_4)建立了高灵敏的连续测定铜和锌的荧光煽灭法。以Cd(Ⅰ)和2,2′-联吡啶作联合催化剂,在碱性条件下测得铜、锌总量,然后在酸性条件下测得铜的含量。并由此计算出锌的含量。铜、锌的检测限分别达2.3ng/ml和1.0ng/ml。应用手环境水样中铜、锌连续测定,结果满意。     

Calculation of Plane Vibration Frequencies of the Porphin Molecule

By the DFT/B3LYP method with a 6-31G^** basis set the frequencies of normal vibrations of porphin and its five derivatives have been calculated. Scaling of the force constants for plane vibrations in independent natural coordinates has been carried out. Symmetry coordinates have been introduced and a force field for plane vibrations of the porphin molecule in independent symmetry coordinates has been obtained. Based on an analysis of special matrices and the potential energy distribution, complete matching of the plane vibration frequencies of porphin and its four isotopomers has been performed.     

密度泛函理论研究-卟吩二聚体几何结构与结合能

用密度泛函理论ωB97XD/cc-pVDZ,对卟吩可能存在的二聚体进行了几何优化,得到4种该二聚体的稳定构型D、E、F和G(其中G为晶体X衍射实验构型),计算出其结合能ΔE分别为-24.36、-24.87、24.50和-23.31kcal/mol。     

TPPS4浸渍树脂对镉吸附性能的研究

本文用ｍｅｓｏ－四（４－碳酸苯基）卟啉处理１３００－Ⅱ型大孔吸附树脂制得县有相应卟啉基团的浸渍树脂（ＴＰＰＳ４浸渍树脂），并用静态法求得ＴＰＰＳ４浸渍树脂吸附镉的最佳ｐＨ，平衡速率、吸附容量、吸附物组成及热力学函数等．