BH分子X 1Σ+、A 1Π和B 1Σ+ 态的势能函数

利用SAC/SAC-CI方法，使用D95++、6-311++g及cc-PVTZ等基组，对BH分子的基态(X ¹Σ⁺)、第一简并激发态(A ¹Π)及第二激发态(B ¹Σ⁺)的平衡结构和谐振频率进行了优化计算． 通过对三个基组计算结果的比较，得出了cc-PVTZ基组为三个基组中的最优基组的结论；使用cc-PVTZ基组，利用SAC的GSUM(group sum of operators)方法对基态(X ¹Σ⁺)， SAC-CI的GSUM方法对激发态(A ¹Π 和B ¹Σ⁺)进行单点能扫描计算, 用正规方程组拟合Murrell-Sorbie函数，得到了相应电子态的完整势能函数；从得到的势能函数计算了与基态(X ¹Σ⁺)、第一简并的激发态(A ¹Π)和第二激发态(X ¹Σ⁺)相对应的光谱常数(Be、αe、ωe 和ωeχe)，结果与实验数据较为一致． 其中基态、第一激发态与实验数据吻合得较好．     

KBn（n=1～10）团簇的结构和性质的密度泛函理论研究北大核心CSCD

应用密度泛函理论（DFT）B3LYP方法在6-311＋G（d）水平上计算并分析了KBn（n=1～10）团簇的几何结构及电子性质和极化率．通过研究团簇的平均结合能、能级间隙、二阶能量差分分析了团簇的稳定性规律,研究表明：KBn（n=1～10）团簇基态多数为立体构型,能级间隙和二阶能量差分结果表明KB3 与KB9是幻数团簇．对团簇基态的极化率研究表明KB。团簇的电子结构随B原子的增加趋于紧凑,基本形成了一定的堆积方式．静态第一超极化率研究表明K战与KB4两种平面构型的团簇具有较好的非线性光学性能。     

Li2Bn(n=1～10)团簇的几何结构和电子性质

应用密度泛函理论(DFT)B3LYP方法在6-311+G(d)水平上计算并分析Li2Bn(n=1～10)团簇的平均结合能、能级间隙、二阶能量差分和极化率等物理化学性质.由此讨论了团簇的几何结构和电子性质.研究表明:Li2Bn(n=1～10)团簇基态大多为主体构型,能级间隙和二阶能量差分结果表明Li2B8为幻数团簇.对平均线性极化率和极化率的各向异性不变量研究表明,基态Li2Bn团簇的电子结构随B原子的增加虽然趋于紧凑,但尚未形成特定的堆积方式.     

自辐射场下PuO2分子光谱研究

在相对论有效原子实势（RECP）近似下,采用优选的密度泛函 B3P86方法,研究了钚本身产生自辐射场（-0.005～0.005a.u.）作用下PuO2基态分子的能隙Eg和谐振频率ν.结果表明：能隙Eg＝3.157eV,接近实验值1.8eV,PuO2在自辐射场中具有半导体性质;反对称伸缩振动频率ν3(σg)、弯曲振动频率ν2(πu)和对称伸缩振动频率ν1(σg)与实验值794.3 cm-1、230.2、746.5cm-1基本吻合.     

The analytical potential energy function of flue gas SO₂（X¹A₁）

The equilibrium structure of flue gas SO 2 is optimized using the density functional theory (DFT)/ B3P86 method and CC-PV5Z basis. The result shows that it has a bent (C2V ,X1A1) ground state structure with an angle of 119.1184 . The vibronic frequencies and the force constants are also calculated. Based on the principles of atomic and molecular reaction statics (AMRS), the possible electronic states and reasonable dissociation limits for the ground state of SO2 molecule are determined. The potential functions of SO and O2 are fitted by the modified Murrell–Sorbie+c6 (M-S+c6) potential function and the fitted parameters, the force constants and the spectroscopic constants are obtained, which are all close to the experimental values. The analytic potential energy function of the SO2 (X1A1) molecule is derived using the many-body expansion theory. The contour lines are constructed, which show the static properties of SO2 (X1A1), such as the equilibrium structure, the lowest energies, the most possible reaction channel, etc.     

Molecular properties and potential energy function model of BH under external electric field

Using the density functional B3P86/cc-PV5Z method, the geometric structure of BH molecule under different external electric fields is optimized, and the bond lengths, dipole moments, vibration frequencies, and other physical properties parameters are obtained. On the basis of setting appropriate parameters, scanning single point energies are obtained by the same method and the potential energy curves under different external fields are also obtained. These results show that the physical property parameters and potential energy curves may change with external electric field, especially in the case of reverse direction electric field. The potential energy function without external electric field is fitted by Morse potential, and the fitting parameters are obtained which are in good agreement with experimental values. In order to obtain the critical dissociation electric parameter, the dipole approximation is adopted to construct a potential model fitting the corresponding potential energy curve of the external electric field. It is found that the fitted critical dissociation electric parameter is consistent with numerical calculation, so that the constructed model is reliable and accurate. These results will provide important theoretical and experimental reference for further studying the molecular spectrum, dynamics, and molecular cooling with Stark effect.     

NiCO分子结构与解析势能函数

用密度泛函理论的B3P86方法,对镍原子采用LANL2DZ收缩价基,碳原子和氧原子采用6-311+G~*基组,对NiC、NiO和NiCO体系的结构进行优化,计算表明:NiC分子基态为~1∑~+态,键长为R_e=0.16070 nm,离解能为3.62948 eV.NiO分子基态的平衡核间距为0.16784 nm,其电子态为~3∑~-,离解能为3.45119 eV,拟合得到Murrell-Sorbie势能函数;NiCO分子有两个线性稳定构型,其中一个构型为Ni—C≡O(C_(∞υ)),电子态为~1∑~+,平衡核间距为R_(NiC)=0.16621 nm,R_(co)=0.11519 nm,离解能为12.80476 eV,另一个为Ni—O≡C(C_(∞υ)),电子态是~1∑~+,平衡核间距为R_(co)=0.11470 nm,R_(NiO)=0.17636 nm,离解能为11.24679 eV.由微观过程的可逆性原理分析了分子的可能的离解极限,并用多体展式理论导出基态NiCO分子的势能函数,其等势面图准确地再现了NiCO分子的结构特征和离解能,由此讨论了Ni+CO,NiC+O,NiO+C分子反应的势能面静态特征.     

PuO分子激发态的外场效应

在相对论有效原子实势近似下,用B3LYP密度泛函方法计算优化得到了分子轴方向不同电场(-0.005~0.005a.u.)作用下,PuO的基态C∞V(X7-)几何结构、偶极矩和分子总能量。在优化构型下,用同样的基组采用含时密度泛函(TDDFT)方法(TD-B3LYP),研究了同样外电场条件下,对PuO的激发能的影响。计算结果表明,在外场作用下,对PuO的前5个激发态电子跃迁光谱属于远红外光谱,波长为2 064.7~18 900.0nm,这是钚原子的奇异特征;激发能与外电场的关系近似满足Grozema等人提出的关系。     

基于丙烯酰胺为单体的红敏光致聚合物衍射效率增强的研究

目前以丙烯酰胺为单体的光聚物体系在高分辨力下衍射效率不高。从光聚物聚合机理出发．探讨了其主要原因。从单体聚合难易程度角度提出了加入新成分丙烯酸、使用聚合度低的成膜物、增加膜的厚度和优化凉板时间等四种促进单体聚合的措施并从实验上加以了验证。结果表明：在一定条件下。成膜物使用聚合度为341的聚乙烯醇比聚合度为1750的聚乙烯醇体系衍射效率提高了约60％;加入丙烯酸后衍射效率也提高了10％左右,且使用聚合度低的成膜物和加入丙烯酸后体系更不易结晶;厚度和凉板时间均有一个最佳范围。经过优化实验后得到了空间频率在2000lp／mm时衍射效率大于90％,3000lp／mm时大于55％的结果,且利用制备出的材料拍摄出透射和平面反射全息网,说明该材料适合于日益发展的全息显示。