[Cl3Sb（u0S）sBCl3]^2—阴离子的红外光谱和简正坐标分析

在500－100cm^-1波段范围内测定了[Cl3Sb(u-S)SbCl3]2-阴离子的Fourier变换红外光谱，采用简化的普遍价力场（SGVFF）进行了简正坐标分析，振动基频的计算值与观测值符合良好，两者平均差小于1．0％，证实了振动谱带的归属，确定了相应的力常数，最后讨论了谱带归属问题和所得结果的合理性和可靠性。     

十五种稀土草酸盐水合物的Fourier变换远红外光谱与简正坐标分析

本文研究了除Pm和Sc以外整个稀土系列草酸盐水合物在100—400cm~(-1)范围的Fourier变换远红外光谱。应用NORVIB程序,在简正坐标分析的基础上,对振动频率作了指认。对La至Eu的含水草酸盐络合物,红外分析所采用的结构模型依据Nd_2(C_2O_4)_(?)·10H_2O的晶体结构确定,即每个稀土离子周围有九个氧原子,六个氧原子来自三个草酸根离子,其余三个氧原子由水分子提供。对Gd至Lu以及Y的含水草酸盐络合物,则依据Yb_2(C_2O_4)_3·6H_2O的晶体结构确定,即每个稀土离子周围有八个氧原子,六个氧原子来自三个草酸根离子,其余二个氧原子由水分子提供。作图示出金属-配体的振动频率及力常数随镧系原子序数的变化关系,并对此作了讨论。#原图像不清楚     

FC(O)NCS 分子振动光谱的理论研究

采用DFT(B3LYP)方法,以6-3G*为基组对FC(O)NCS的顺式和反式两种构型的几何结构,振动谐性力场和红外光谱进行了研究。B3LYP/6-31G*计算水平和大多数有机分子的一套固定标度因子进行标度。根据标度后的理论力场进行简正坐标分析得到的势能分布(PED)和红外光谱强度值对FC(O)NCS分子的顺式和反式两种构型的振动基频进行了理论归属。     

ClC(O)NCS分子振动光谱的理论研究

采用密度泛函理论DFT(B3LYP)方法,以6-31G^*为基组对ClC(O)NCS的反式和顺式两种构型的几何结构、振动谐性力场和红外光谱进行了研究.B3LYP/6-31G^*的理论力场由适用于B3LYP/6-31G^*计算水平和大多数有机分子的一套固定标度因子进行标度.根据标度后的理论力场进行简正坐标分析得到的势能分布(PED)和红外光谱强度值对ClC(O)NCS分子的顺式和反式两种构型的振动基频进行了理论归属.     

CO(υ)高振动激发态向C_2H_2的振动传能研究

用时间分辨窝里叶红外发射谱研究了高振动激发态CO向C2H2的传能，得到了CO（v＝1－3）各振动态布展及其随时间的变化,利用微分法解出弛豫微分方程组，获得CO（v=1-3）向C2H2的传能速率常数分别为：2．0±0．1，6.0±0．2和9．1±0.8（10-13cm3·molecule-1·s-1）．传能速率随着振动量子数的增加而迅速增加．CO的振动能应向C2H2的对称伸缩模v2近共振V－V传递．传能过程中还可能形成二聚体络合物，加速了CO（v）向C2H2的传能．用abinitio方法确定了CO...C2H2两种可能的直线构型．     

1,4—二羟蒽醌红外光谱的振动分析

测量了１，４－羟基蒽醌及其氘化物的红外光谱，用ＮＲＣＣ程序进行了振动分析，由于同时考虑了分子内与分子间的氢键，统一处理面内与面外振动，计算结果优于文献报道，并纠正了一些错误归属。     

稀土二苯甲酰甲烷螯合物Ln(DBM)3·H2O振动光谱的简正坐标分析

本文报道了Ln(DBM)_3·H_2O的简正坐标分析结果, 计算中采用了单螯合坏近似模型, 计算结果和红外、拉曼光谱观测频率符合较好, 所得到的一组力常数, 具有较好的转移性质. 讨论了一些重要谱带的性质。     

2-甲基-,1-环丙烷二羧酸根乙二胺合铂(II)的晶体结构和振动光谱的简正坐标分析

测定2-甲基-1,1-环丙烷二羧酸根乙二胺合铂(II)([PtenMCPDA])的晶体结构。晶体属正交晶系, 空间群为pn21α, 晶胞参数: a=0.9075(4), b=.0247(4), c=11.394(5)nm;分析Patterson函数, 找到原子坐标, 经差值fourier合成得到全部非氢原子坐标, 用最小二乘法修正, 最终R因子为0.0706。采用U-B力场进行了[Pten MCPDA]的分子简正坐标分析, 振动基频的计算值与观测值相符合, 两者平均偏差6.67cm^-^1, 最大误差16.1cm^-^1, 证实了振动光谱的归属。     

去氢抗坏血酸分子振动光谱的理论研究

采用RHF, MP2, DFT(B3LYP)方法, 以6-311++G**为基组研究了去氢抗坏血酸分子(DHA)的平衡几何构型和振动光谱. 计算结果表明, 采用RHF, B3LYP以及MP2 方法优化得到的几何结构以及频率值是一致的. 采用B3LYP/6-311++G**计算了DHA分子平衡构型下的谐振动力场﹑振动频率和振动强度. 使用Wilson的GF矩阵方法对DHA分子进行了简正坐标分析, 依据所得的势能分布对DHA分子的振动基频进行了合理的理论归属.     

2-甲基-,1-环丙烷二羧酸根乙二胺合铂(II)的晶体结构和振动光谱的简正坐标分析

测定2-甲基-1,1-环丙烷二羧酸根乙二胺合铂(II)([PtenMCPDA])的晶体结构。晶体属正交晶系, 空间群为pn21α, 晶胞参数: a=0.9075(4), b=.0247(4), c=11.394(5)nm;分析Patterson函数, 找到原子坐标, 经差值fourier合成得到全部非氢原子坐标, 用最小二乘法修正, 最终R因子为0.0706。采用U-B力场进行了[Pten MCPDA]的分子简正坐标分析, 振动基频的计算值与观测值相符合, 两者平均偏差6.67cm^-^1, 最大误差16.1cm^-^1, 证实了振动光谱的归属。     

NORMAL VIBRATIONAL ANALYSIS OF TRANS-POLYACETYLENE

The results of normal vibrational analyses of trans, trans-2, 4-hexadiene and the backbone of trans, trans-1, 4-diphenyl-butadiene were used in the normal mode computation of trans-polyacetylene (PA). Only 8 non-zero calculated frequencies were obtained which obeys the rule of 3N-4. The potential energy distribution (PED) data were in good agreement with the empirical assignment of Shirakawa et al. and Kozmany, but most of the vibrational frequencies of trans-PA had contributions from several empirical modes, indicationg the more complieacy in trans-PA molecular vibration than in the model molecule case. The calculated C=C and C—C stretching frequencies of trans-PA were over 200cm~(-1) higher and lower than the observed ones, respectively, due to the longer effective conjugate length in the trans-PA. This was shown by the dependence of the PED-weighted average frequencies of C=C and C—C stretchings on the force constants f(C=C)~2 and f(C—C)~2.     

NORMAL VIBRATIONAL ANALYSIS OF CIS-POLYACETYLENE

The normal vibrational calculation was carried out on cis-polyacetylene(PA) and its model compound, cis, trans-2, 4--hexadiene. Based on the observed IR and Raman frequencies, force constants relevant to the cis-structure were refined. Finally a force field common for cis-PA, trans-PA and three model moleculaes was obtained. The observed spectra of cis-PA were theoretically assigned and the similarities and differences between the cis-and trans- conjugate systems were discussed on the basis of normal coordinate calculation.     

1,1—环丙烷二羧酸根二氨合铂的晶体结构和振动光谱的简正坐标分析

测定了1,1-环丙烷二羧酸根二氨合铂([Pt(NH_3)_2CPrDCA]·H_2O)的晶体结构。晶体属正交晶系,空间群为Pnma,a=6.571(2),b=9.709(3),c=14.205(5)A,Z=4。用Patterson函数导出Pt原子坐标,经差值Fourier合成获得全部非氢原子坐标,用最小二乘法修正,最终R因子为0.058,采用U-B力场进行了[Pt(NH_3)_2CPrDCA]分子的简正坐标分析,振动基频的计算值与观测值符合,两者平均偏差5.63cm~(-1),最大误差15.7cm~(-1),证实了振动光谱的归属。     

1,1-环丙烷二羧酸根二氨合铂的晶体结构和振动光谱的简正坐标分析

测定了1,1-环丙烷二羧酸根二氨合铂([Pt(NH₃)₂CPrDCA]·H₂O)的晶体结构。晶体属正交晶系,空间群为Pnma,a=6.571(2),b=9.709(3),c=14.205(5)Å,Z=4。用Patterson函数导出Pt原子坐标,经差值Fourier合成获得全部非氢原子坐标,用最小二乘法修正,最终R因子为0.058,采用U-B力场进行了[Pt(NH₃)₂CPrDCA]分子的简正坐标分析,振动基频的计算值与观测值符合,两者平均偏差5.63cm^-1,最大误差15.7cm^-1,证实了振动光谱的归属。     

Darstellung,Schwingungsspektren und Normalkoordinatenanalyse der Halogenonitrosylruthenate [Ru(NO)ClnBr5–n]2–, n = 0–5, sowie die Kristallstruktur von (CH2py2)[Ru(NO)ClBr4]

Syntheses, Vibrational Spectra, and Normal Coordinate Analysis of Halogenonitrosylruthenates [Ru(NO)Cl_nBr_5–n]^2–, n = 0–5, and the Crystal Structure of (CH₂py₂)[Ru(NO)ClBr₄] By treatment of [Ru(NO)Cl₅]^2– with anhydrous HBr in dichloromethane a mixture of [Ru(NO)Cl_nBr_5–n]^2–, n = 0–5, is formed, from which individual complexes can be separated by ion exchange chromatography on diethylaminoethyl cellulose. The X-Ray structure determination on a single crystal of (CH₂py₂)[Ru(NO)ClBr₄] (monoclinic, space group P2₁/c, a = 11.480(2), b = 10.175(4), c = 16.025(6) Å, β = 107.40(1)°, Z = 4) reveals, that the chlorine atom is trans positioned to the nitrosyl group. The low temperature IR and Raman spectra have been recorded of six complexes of the series (n-Bu₄N)₂[Ru(NO)Cl_nBr_5–n], n = 0–5, and are assigned by normal coordinate analysis. A good agreement between observed and calculated frequencies is achieved. The valence force constants are f_d(NO) = 13.86–13.93 und f_d(RuN) = 5.43–5.49 mdyn/Å.     

FOURIER TRANSFORM FAR INFRARED SPECTRA AND NORMAL COORDINATE ANALYSIS OF FIFTEEN RARE-EARTH OXALATE HYDRATES

The Fourier transform far infrared spectra of oxalate hydrates of whole rare-earth series except Pm and Sc are investigated in the range of 100-400 cm~(-1). The assignment of vibrational frequencies is made on the basis of normal coordinate analysis using our NORVIB program. The model used for the hghter elements of the lanthanide series (La to Eu) is based on the crystal structure of Nd_2(C_2O_4)_3. 10H_2O, in which each lanthanide ion is surrounded by nine O atoms, six from three oxalate ions and three from Water molecules.The model adopted for the heavier elements of the lanthanide series (Gd to Lu) and Ytterbium is based on the crystal structure of Yb_2(C_2O_4)_3· 6H_2O, in which each ion is surrounded by eight atoms, six from three oxalate ions and two from water molecules. The variation of the metal-ligand frequencies and force constants with the atomic numbers of lanthanides is plotted and discussed.     

FT-Raman and FTIR spectra, normal coordinate analysis and ab initio computations of (2-methylphenoxy)acetic acid dimer

The Fourier Transform Raman and infrared spectra of the crystallized herbicide (2-methylphenoxy)acetic acid (MPA) have been recorded in the region 4000–400 cm⁻¹. The geometry, intermolecular hydrogen bond, and harmonic vibrational frequencies of MPA have been investigated with the help of B3LYP density functional theory (DFT) methods. The calculated molecular geometry has been compared with the experimental data obtained from XRD data. The assignments of the vibrational spectra have been carried out with the aid of normal coordinate analysis (NCA) following the scaled quantum mechanical force field methodology (SQMFF). The strong doubly hydrogen bonded interface of the dimerized system is well demonstrated by the red shift in OH stretching frequency concomitant with the elongation of bond length. The most stable structure of the dimer possesses center of symmetry and interaction energy of −83.642 kJ mol⁻¹ after the basis set superposition error (BSSE) correction by the counterpoise (CP) method. The natural bond orbital analysis (NBO) ascertains that the delocalization of unpaired electron of oxygen atom onto the CO bond causes double bond character.     

NORMAL COORDINATE ANALYSIS OF DINUCLEAR MOLYBDENUM COMPLEX UNIT Mo_2O_2(μ-S)_2(dtcR_2)_2

<正> INTRODUCTION. The empirical assignments of vibrational spectra of Mo_2O_2(u-S)_2(dtcR_2)_2 have been reported. It is necessary to assign the spectra by theoretical calculation for better understanding molecular structureand chemical bonding of the complexes. We report normal analysis of thetitle unit in this paper.