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1.
吉非替尼是第一个被批准上市用于治疗晚期非小细胞肺癌(NSCLC)的药物.该文采用5种密度泛函理论(DFT)方法B3LYP,BHandHLYP,M06-2X,CAM-B3LYP和LC-wPBE在6-311++G**水平上对吉非替尼分子的红外、紫外可见光谱及核磁共振谱进行了计算,并通过比较计算值和实验值得到最佳的计算条件.研究结果表明,CAM-B3LYP和M06-2X是最佳的用于描述吉非替尼分子红外光谱的方法;B3LYP//GIAO(Gauge-Including Atomic Orbital)方法预测得到的吉非替尼在(CH3)2SO中的1H NMR与实验值最为接近,用于预测13C NMR的最佳方法是B3LYP//CSGT(Circularty Sgmmetrical Gabor Transform).  相似文献   

2.
提出了一种基于密度泛函理论计算晶体结合能的变分法,利用该方法初步计算了LiF、NaF、KF、LiCl、NaCl和KCl这六种典型离子晶体的结合能、平衡晶格常数和体弹性模量,与实验结果进行了比较,分析了存在的问题,并指出了与其它同类方法相比该方法的优点  相似文献   

3.
4.
氮的三原子化合物的从头算及密度泛函研究   总被引:1,自引:0,他引:1  
在6-311+G*基组水平上,对氮的三原子化合物N3^-、N3、N3^+,用MP2及六种密度泛涵方法进行了研究。结果表明,对于已知结构的化合物和计算结果与实验测定值非常吻合,对实验上未知的化合物分子的稳定几何构型及其有关参数进行了新的探讨和补充,同时比较了N3^-、N3、N3^+间相对稳定性和几何性质,并讨论了几种不同方法对该化合物系列诸性质参数的影响,结合MO理论及成键能的计算结果进行了成键分析。  相似文献   

5.
应用密度泛函理论方法 (B3LYP)和QCISD方法 ,对N2 …HF弱结合复合体系在不同的基组下进行abinitio计算 ,得到了该复合物分子分别在QCISD及B3LYP水平下的平衡结构为 :RNN=0 .110 4nm ,0 .10 95nm ,RNN=0 .2 198nm ,0 .2 0 94nm和RHF=0 .0 92 2nm ,0 .0 931nm ,计算了复合物中HF的谐振频率为 3899.399cm-1以及HF谐振频率红移量为 6 2 .75 5cm-1,所计算的结果与近期的实验数据和理论值相符合 ,还考查了不同基组和方法对N2 …HF弱结合体系的影响  相似文献   

6.
光纤光栅可以看作为周期性高、低折射率相间的多层落膜叠合结构。用波动方法推导了计算这一结构总反射系数的一个新的循环公式。用这一方法计算了均匀光纤光栅布格拉格相位匹配、失配情况和非均匀光纤光栅的反射系数,并将其结果与用耦合波理论、Rouard方法以及基础矩阵方法的结果进行了比较,并检验了这些方法的精度。  相似文献   

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8.
A doubleness symmetry property of the two-dimensional reduced Einstein-Maxwell-dilaton theory is found and, by using the so-called extended double complex method proposed previously, the motion equations of the theory are extended into a double form. Some new double symmetry transformations and double solution generating methods are given. As applications of these transformations and methods, an infinite chain of double solutions and a new soliton double solution family of the model are obtained. These results demonstrate that the theory under consideration possesses more and richer symmetry structures than previously expected. It seems that some of these results can not be obtained by using only the usual (non-double) scheme.  相似文献   

9.
The electronic, optical and thermodynamic properties of ZnS in the zinc-blende (ZB) and wurtzite (WZ) structures are investigated by using the plane-wave pseudopotential density functional theory (DFT). The results obtained are consistent with other theoretical results and the available experimental data. When the pressures are above 20.5 and 27 GPa, the ZB-ZnS and the WZ-ZnS are converted into indirect gap semiconductors, respectively. The critical point structure of the frequency-dependent complex dielectric function is investigated and analysed to identify the optical transitions. Moreover, the values of heat capacity Cv and Debye temperature θ at different pressures and different temperatures are also obtained successfully.  相似文献   

10.
The dual-phase-lag (DPL) model with two different time translations and Lord–Shulman (LS) theory with one relaxation time are applied to study the effect of hydrostatic initial stress on medium under the influence of two temperature parameter(a new model will be introduced using two temperature theory) and photothermal theory. We solved the thermal loading at the free surface in the semi-infinite semiconducting medium-coupled plasma waves with the effect of mechanical force during a photothermal process. The exact expressions of the considered variables are obtained using normal mode analysis also the two temperature coefficient ratios were obtained analytically. Numerical results for the field quantities are given in the physical domain and illustrated graphically under the effects of several parameters. Comparisons are made between the results of the two different models with and without two temperature parameter, and for two different values of the hydrostatic initial stress. A comparison is carried out between the considered variables as calculated from the generalized thermoelasticity based on the DPL model and the LS theory in the absence and presence of the thermoelastic and thermoelectric coupling parameters.  相似文献   

11.
能带论自洽LMTO方法计算金属铜的零温物态方程   总被引:1,自引:1,他引:1  
 用密度泛函框架下的自洽LMTO方法,在计算一系列晶格常数的Cu的能带结构的基础上,计算了Cu的零温物态方程。压缩度为1.0~4.5。计算结果与两种基于实验数据的半经验方法所得结果以及Albers等人的计算结果进行了比较,其高压部分亦与带量子交换修正的TFC模型结果作了比较,说明计算结果是合理的。进一步的研究可为修正半经验方法提供依据。弄清与TFC理论的异同,对多体系统相互作用有更进一步的了解。  相似文献   

12.
孕周的超声无损估计   总被引:1,自引:0,他引:1       下载免费PDF全文
本文讨论了孕周的超声无损估计方法,传统上,对孕周的估计是通过B型超声测量胎儿器官的有关参数,辅以经验公式而得到。但是由于经验公式无统一形式,且参数皆单独使用,估计结果离散度大,难以实用化。本文对B型超声测量所得胎儿参数应用数量化理论,建立孕周自动估计的方法。由于在实际应用中,应用数量比理论所得的相应正规方程,难以满足通常求解方法的前提条件,本文引入广义逆矩阵理论求解正规方程。另外,本文进一步讨论了  相似文献   

13.
李雪梅  韩会磊  何光普 《物理学报》2011,60(8):87104-087104
采用基于密度泛函理论的平面波赝势方法,在局域密度近似下采用线性响应的密度泛函微扰理论计算了LiNH2的晶格动力学、介电性质和热力学性质,得到了布里渊区高对称方向上的声子色散曲线和相应的声子态密度,分析了 LiNH2的红外和拉曼活性声子频率,同时给出它的介电张量和玻恩有效电荷张量. 研究表明,LiNH2存在小的各向异性,计算所得结果与实验值和其他理论值符合较好.最后,利用得到的声子态密度进一步预测了LiNH2的热力学性质 关键词: 密度泛函理论 晶格动力学 热力学性质 第一性原理计算  相似文献   

14.
Self-consistent band calculations on four intermetallic compounds of the CsCl structure are presented. The calculations were performed employing the self-consistent ultrasoft pseudopotential method based on the density functional theory, within the local density approximation and the generalized gradient approximation. The calculations predicted that the equilibrium lattice constants are in excellent agreement with the experiment for CoAl and are 1% smaller than experimental values for CoBe, CoSc and CoZr, respectively. In the present study, ordered CoAl do not show any magnetic moment, whereas the other three compounds have moderate magnetic moments of about 0.2 and 0.7 Bohr magnetons (μB ) per atom. The elastic constants are calculated using two approaches, the energy-strain method and the use of phonon dispersion curves. The values obtained from the two methods are in reasonable agreement for the studied intermetallic compounds CoZ (Z?=?Al, Be, Sc and Zr). The brittleness and ductility properties of CoZ (Z?=?Al, Be, Sc and Zr) are determined by Poisson’s ratio σ criterion and Pugh’s criterion. The calculated elastic constants satisfy the mechanical stability criterion and the ductility of CoZr and CoSc is predicted by Pugh’s criterion. The band structure and density of states, and phonon dispersion curves have been obtained and compared with the available experimental results as well as with existing theoretical calculations. We studied and discussed the position of Fermi level for the selected four intermetallic compounds.  相似文献   

15.
魏洪源  熊晓玲  刘国平  罗顺忠 《物理学报》2011,60(6):63401-063401
应用群论及原子分子反应静力学方法推导了TiO分子基态(X3Δr)的离解极限.采用不同的计算方法,包括密度泛函B3LYP,B3P86,BP86,B3PW91和MP2,MP4方法,结合不同基组计算了TiO分子基态的平衡核间距、能量和振动频率.研究表明,使用B3LYP方法,对O原子使用6-311+G基组,Ti原子使用6-311+ +G**基组时计算得到的平衡几何结构、分子离解能和谐振频率与实验值符合得最好.使用优选出的方法和基组对T 关键词: TiO 势能函数 光谱常数 密度泛函理论  相似文献   

16.
王子华  吴智勇 《光子学报》1997,26(2):115-120
本文应用耦合波理论来计算任意渐变折射李光纤的传播常数和模场分布.将无限伸展的抛物型折射率分布光纤作为一个理想波导,任意径向不均匀折射率分布光纤便可以视作该理想波导的微扰,其模场可以展开成一组完备的理想波导模的叠加.然后,模场和传播常数可以通过耦合波方程求得.进一步将一阶微分方程组形式的耦合波方程变换成线性方程组,使计算过程大大简化.文中给出了数值计算结果,并将其与准确值进行了比较.  相似文献   

17.
基于Bohr-Sommerfeld量子理论的X射线光谱分析   总被引:3,自引:0,他引:3       下载免费PDF全文
余志强  谢泉  肖清泉  赵珂杰 《物理学报》2009,58(8):5318-5322
基于Bohr-Sommerfeld量子理论,研究了特征X射线的产生机理,导出了一个按原子序数来计算特征X射线波长的公式.同时对计算推导的波长值做了系统的误差分析,得到了相对误差的规律.结果表明,计算推导的波长值与实验得到的波长值非常接近,并且在实际应用中该公式也更为简便. 关键词: Bohr-Sommerfeld量子理论 特征X射线 波长 误差分析  相似文献   

18.
王力鸣  侯洵 《光学学报》1992,12(2):68-174
将三阶微扰理论应用于单晶GaAs半导体,结合与实际相接近的能带结构,得到了GaAs中三光子吸收系数的解析式表达式,在考虑了激发电子的逃逸过程的情况下,进而推导了负电子亲和势GaAs光电阴极中三光子光电发射的发射系数的解析表达式.两表达式得到的理论数值分别与用ns量级脉宽、2.06μm波长的激光测得的GaAs中三光子吸收系数和GaAs(Cs,O)光电阴极中三光子发射系数的实验值相比较,吻合较好.  相似文献   

19.
The long time tails of the correlation functions that determine the self-diffusion coefficient and the kinetic parts of the shear viscosity and heat conductivity in a one-component plasma are calculated using a systematic kinetic theory. The results are in agreement with those obtained from the phenomenological mode coupling theory. The formal kinetic theory calculations of previous workers, who obtained incomplete long time tail results, are also discussed.  相似文献   

20.
采用密度泛函方法研究了从细梗胡枝子中提取的三种新型抗氧化剂的分子结构和活性氧清除机理.研究发现优化后的最优分子构型中都含有分子内氢键,与用二级微扰方法得到的结果一致.根据预测的气相和水相抗氧化剂的键解离能、电离势,以及三种重要活性氧的电子亲和势和氢原子亲和势,详细讨论了三种抗氧化剂的活性氧清除机理并发现其抗氧化活性和实验结果一致.  相似文献   

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