Based on the two conformers of enamines, four different reaction pathways have been considered.

The result shows that MP2, QCISD, B3LYP can gain the gauche and anti conformers of oxalyl iodide, which is in good agreement with configuration of oxalyl halides in experiment.

结果表明，在不同基组水平上，由MP2，QCISD，B3LYP方法均能得到草酰碘分子的交叉式构型和平面反式构型，与实验所得草酰卤化物的构型完全相符。

In this study, the effects of the column temperature, pH, flow rate, silica gel, stationary phase and pairing ion on the peak profile and the separation of the panipenem conformers were investigated qualitatively.

本文定性地研究了柱温、pH、流速、硅胶、固定相和对离子等对帕尼培南峰形和构象异构体分离的影响。

The tensile property test shows that the tensile modulus of samples is decreased after degradation in all conditions, which is related to the decrease of crystallinity and conform change of trimethylene glycol conformers during degradation.

拉伸试验证明了试样在各条件下降解后拉伸模量降低，这与试样在降解后结晶度降低和丙二醇基团的邻位交叉构象增多有关。

In addition, the result derived from G3MP2 shows that the heats of formation of all conformers are positive and heats of formation of ring con-formers are greater than those of chain conformers.

G3MP2计算结果表明氮氢化合物的生成热均为正，并且环状分子的能量和生成热都高于链状分子。

But the conventional CoMFA exists some defects, including the selection of potential function of molecular field, the determination of bioactive conformers, the molecular alignment and the selection of variable of molecular fields, etc.

但传统的比较分子场分析方法在具体的实现过程中还存在着一些缺陷和不足，包括分子场势能函数的选择，活性构象的确定，分子的叠合以及分子场变量的选取等等。

Proteins are inherently plastic molecules, whose function often critically depends on excursions between different molecular conformations ( conformers).

蛋白质是固有的柔性分子，其功能往往关键取决于不同分子构象之间变化。

Furthermore, we also found the presence of a variety conformers in solution of capecitabine and trandolapril, and then elucidated its stereostructure by NMR spectroscopy and quantum chemistry calculation for the first time.

同时，本研究首次发现群多普利和卡培他滨在溶液中存在多种构象异构体，并通过NMR实验和量子化学计算阐明了其立体结构。

Compared with the other three conformers, calix [ 4] arenes in the 1,2-alternate conformation were less reported, mainly due to the lack of a satisfactory preparation method.

与其它三种构象相比较，1,2-交替构象的杯[4]芳烃较少被报道，主要原因还是缺少令人满意的制备方法。

So far, though there have been increasing examples of inherently chiral calix [ 4] arenes with various substitution patterns ( upper and/ or lower rim, meta-position) and novel structures, most of them are cone and partial cone conformers.

至今已有大量上沿、下沿或间位取代的固有手性杯[4]芳烃被合成出来，但其中大部分都是锥形或部分锥形构象。

O??? Those who are 'conformers' typically have high levels of anxiety, low status, high need for approval and often authoritarian personalities.

那些人云亦云者典型地感到非常焦虑，地位低下，并且很需要认同感，时常有权力主义的性格。

DFT study on the conformers and C-C bond reaction activity of oxalyl bromide cation

草酰溴一价正离子（BrCO）2~+几何构型及反应活性的DFT研究

Surface tension, density distribution, number density distribution, charge distribution, radium distribution function, diffusion and conformers of carbon chain have been analyzed to study the effect of Ca and Mg ions. 5.

通过计算表面张力，密度分布，数密度分布，电荷分布，径向分布函数，扩散系数以及尾链构象的分析，研究Ca，Mg离子对表面活性剂的影响。

Comparing with the relative energies of the alanine-α-pentapeptide conformers obtained by B3LYP/ 6-31G method, it can be concluded that the special hydrogen method is quite reasonable for prediction of the conformation stability of alanine-α-pentapeptides.

利用特殊氢方法定量预测丙氨酸-α-五肽分子65个低能构象的相对稳定性，与B3LYP/6-31G方法比较，得到了满意的结果。

This result agrees with the calculated value 71.48 kJ/ mol of free energy of activation for the interconversion between the conformers.

由低能量构象转化为高能量构象所需活化能为75.66kJ/mol.这一结果与动态NMR实验计算的71.48kJ/mol活化自由能数值相符。

Different intramolecular hydrogen bond interactions can also significantly change the components of several molecular orbits near HOMO orbital of the asparagine conformers, resulting in a pronounced difference in their vertical ionization energy values.

分子内氢键还可以显著改变天冬酰胺HOMO轨道附近的几个轨道的成分，因而造成不同构型垂直电离能数值有显著差异。

The outcome indicates that the conformers with the boron atom combines with O are relative stable ones with the combination energies of ( 95.5) kJ/ mol and 93.4 kJ/ mol.

结果表明，B与O直接结合的构型比较稳定，其稳定化能分别为955和934kJ/mol。

For larger peptides such as penta-, and hexapeptides, our calculations also show that some of their conformers must undergo significant structural changes, due to the confinement of the host.

对于较大尺寸的肽，比如五肽、六肽，我们的计算也显示了由于受到宿主的限制作用，其某些构象必须经历显著的构象变化。

The relative stability of total 111 conformers of Alanine-glycine tri-and tetra-peptide was estimated by the special hydrogen method and by B3LYP/ 6-31G method.

使用特殊氢方法预测丙氨酸甘氨酸混合三肽和四肽分子共111个构象的相对稳定性，并与B3LYP/6-31G方法的相对能量比较，得到了满意的结果。

Geometries of the isolated donor and acceptor have been optimized using B3LYP/ 6-31G method. Two relative stable conformers P and T of the complex have been obtained with the symmetry of C s.

首先在B3LYP/631G水平上对给体和受体进行构型优化，然后采用优化的给受体构型在Cs对称性下计算得到两种相对稳定的复合物构象P和T。

There are four configurational isomers and every configuration has several different conformers of germacrane derivatives, which tend to exist as the most stable conformers.

吉马烷型倍半萜是众多倍半萜结构骨架类型中最为丰富的一种。