自由基ClO和ClO_2的解析势能函数

运用密度泛函(B3LYP)方法,分别选用6-311+G(3df)和aug-cc-pV6Z基组,对ClO自由基和O_2分子进行了计算,并拟合了其M-S势能函数.采用密度泛函方法(B3LYP)在6-311G(3df)基组下对ClO_2自由基的结构进行了优化计算,得到:ClO_2自由基的稳态结构为C_(2v)构型,电子态为~2B_1、平衡核间距R_(clo)=0.14785 nm、键角/OClO=117.3107°、离解能D_e=2.7552 eV、基态振动频率ν_1(a_1)=451.3423 cm~(-1),v_2(a_1)=970.8289 cm~(-1),ν_3(b_2)=1123.5023 cm~(-1).采用多体项展式理论推导了ClO_2自由基的基态解析势能函数,其等值势能图准确再现了该分子的结构特征及其势阱深度与位置.分析讨论势能面的静态特征时得到:在ClO+O→ClO_2反应中存在两个对称的鞍点,分别位于(0.248 nm,0.152 nm)和(0.152 nm,0.248 nm)处,活化能为5.614 kcal/mol     

基态S和D原子的低能弹性碰撞及SD(X~2Ⅱ)自由基的准确相互作用势与分子常数

使用Gaussian03程序包提供的CCSD(T)理论及Duning等的相关一致基cc-pVnz和aug-cc-pVnZ(n=2,3,4,5),对SD(X~2Ⅱ)自由基的平衡核间距、谐振频率及相互作用势进行了计算,并拟合出了相应的光谱常数.在CCSD(T)/aug-cc-pV5Z理论水平下,光谱常数D_0,D_e,D_e,R_e,ω_e.a_e,B_o及B_e的值分别为3.65730 eV,3.77669 eV,0.13424 cm~(-1),1938.372 cm~(-1),0.09919 cm~(-1),4.88585 cm~(-1)和4.8872 cm~(-1),均与已有的实验结果相符很好.利用在CCSD(T)/aug-cc-pv5Z理论水平下获得的相互作用势,在绝热近似下通过数值求解双原子分子核运动的径向薛定谔方程,找到了J=0时SD(X~2Ⅱ)自由基的全部23个振动态,完整地求出了每一振动态的振动能级及相应的经典转折点、惯性转动常数和离心畸变常数;在1.0×10~(-11)-1.0×10~(-4)a.u.的碰撞能区内通过数值求解原子.原子散射的径向薛定谔方程,研究了基态S原子和基态D原子沿sD(X~2Ⅱ)相互作用势的弹性碰撞,计算了这一弹性碰撞的总截面和各分波截面,分析了各分波截面对总截面的影响.结果表明:总截面的形状主要由S分波截面决定,尽管直到l=4的各分波截面均有形状共振存在,但由于其强度都较弱,全部被湮没在较强的总弹性截面中.

Abstract：

The equilibrium internuclear separations, harmonic frequencies and interaction potentials have been calculated by employing the CCSD(T) theory in combination with the series of the correlation-consistent basis sets, cc-pVnZ and aug-ce-pVnZ (n = 2, 3, 4, 5), of Dunning and co-workers. The potential energy curves are all fitted to the Murrell-Sorbie functions, which are used to determine the spectroscopic parameters. At the CCSD(T)/aug-cc-pV5Z level of theory, the values of D_0, D_e, R_e, w_e, a_e,B_0 are 3.65730 eV, 3.77669 eV, 0.13424 cm~(-1), 1938.372 cm~(-1), 0.09919 cm~(-1) , 4.88585 cm~(-1) and 4.8872 cm~(-1), respectively, which conform almost perfectly with the available measurements. With the analytic interaction potential obtained at the CCSD(T)/aug-cc-pV5Z level of theory, a total of 23 vibrational states has been predicted for the first time when the rotational quantum number J is set to equal zero (J = 0) by solving the radial Schrodinger equation of nuclear motion. The complete vibrational levels, classical turning points, inertial rotation and centrifugal distortion constants are reproduced from the SD (X~2Ⅱ) potential when J = 0. The total and various partial-wave cross sections are calculated for the elastic collisions between the ground-state S and D atoms at energies from 1.0 × 10~(11) to 1.0 × 10~(-4) a.u. when the two atoms approach each other along the SD(X~2Ⅱ) interaction potential. No shape resonances can be found in the total elastic cross sections. The results show that the shape of the total elastic cross sections is mainly dominated by the s-partial wave at very low temperatures. Because of the weakness of the shape resonances coming from various partial waves, they are all covered up by the strong total elastic cross sections.     

非晶锂离子导体B_2O_3-Li_2O—LiCl一Al_2O_3中VO~(2+)的电子自旋共振

两种非晶锂离子导体B_2O_3-0.7Li_2O-0.7LiCl-xAl_2O_3-0.1V_2O_5(x=0.05和0.15)的电子自旋共振谱研究表明:(i)ESR线型是高斯型,证实V_2O_5添加量适当;(ii)超精细结构来源于VO~(2+)络离子,具有四角对称性,属C_(4v)群。越精细耦合张量的平行分量平均值A_∥=0.0175cm~(-1),垂直分量A_⊥=0.0063cm~(-1)。由g_∥(g_⊥)求出其基态~2B_(2g)与第一激发态~2E_g的能级间距△_1=2.46×10~4cm~(-1),基态与第二激发态~2B_(1g)的能级间距△_2=3.03×10~4cm~(-1);(iii)变温实验证实:Al_2O_3组分较少(x=0.05)的非晶ESR强度比x=0.15的非晶高3倍至2倍,而Al_2O_3组分越多则ESR强度随温升下降越小。     

用耦合簇理论及相关一致五重基研究SiH2(X1A1)自由基的解析势能函数

运用单双迭代三重激发耦合簇理论和相关一致五重基对SiH2的基态结构进行了优化,并在优化结构的基础上进行了离解能和振动频率的计算.结果表明:SiH2的基态为C2v结构,平衡核间距RSi-H=0.15163 nm,H-Si-H键的键角α=92.363°,离解能De(HSi-H)=3.2735 eV,频率ν1(a1)=1020.0095 cm -1,ν2(a1)=2074.8742cm-1,ν3(a1)=2076.4762cm-1.这些结果与实验值均较为相符.对H2的基态使用优选出的cc-pV6Z基组、对SiH的基态使用优选出的aug-cc-pV5Z基组进行几何构型与谐振频率的计算并进行单点能扫描,且将扫描结果拟合成了解析的Murrell-Sorbie函数.与实验结果及其他理论计算结果的比较表明,本文关于SiH自由基光谱常数(De,Re,ωe,Be,αe和ωeχe)的计算结果达到了很高的精度.采用多体项展式理论导出了SiH2(C2v,X1A1)自由基的解析势能函数,其等值势能图准确再现了它的离解能和平衡结构特征.同时还给出了SiH2(C2v,X1A1)自由基对称伸缩振动等值势能图中存在的两个对称鞍点,对应于SiH+H→SiH2反应,势垒高度为0.5084 eV.     

碰撞诱导振动能量转移:Cs_2[B~1∏_u(u′=5)]+N_2→Cs_2[B~1∏_u(v′=4,6)]+N_2

利用激光诱导荧光方法研究了Cs_2B~1∏_u[(v′=5)]与N_2的碰撞能量转移.脉冲激光激发Cs_2基态至B~1∏_u[(v′=5)]态,池温保持在410K,N_2气压在1.5×10~2Pa～2.5×10~3Pa之间变化.荧光中含有直接荧光和碰撞转移荧光成分,记录直接荧光B~1∏_u(v′=5)→X~1∑_8~+(v″=0)的时间分辨强度.从荧光强度的对数值给出的直线斜率得到B~1∏_u(v′=5)→X~1∑_8~+(v″=0)的有效寿命,由Stern—Volmer方程,得到B~1∏_u(v′=5)→X~1∑_8~+(v″=0)的辐射寿命为(45±9)ns.B~1∏_u(v′=5)态与N_2碰撞的猝灭总截面为(9.8±1.5)×10~(-15)cm~2.用类似的方法得到B~1∏_u(v′=4,6)能级的辐射寿命.在不同的N_2气压下,测量B~1∏_u(v′=5,4,6)→X~1∑_8~+(v″=0)的时间积分荧光强度,首次得到v′=5→v′=4及v′=5→v′=6的碰撞转移截面分别为(3.9±0.8)×10~(-15)cm~2和(4.1±0.8)×10~(-15)cm~2.     

Optical Oscillator Strengths of Hydrogen Chloride in the Energy Region of 5.5-20 eV

Absolute optical oscillator strength density (OOSD) spectrum of HCl in the valence shell energy region of 5.5-20eV has been determined by the high resolution fast electron energy loss spectrometer (EELS). The optical oscillator strengths for the broad A^1Ⅱ 1^3∑^ dissociation peak and the discrete transitions of b^aⅡ(ν′= 0),C^1Ⅱ ( ν′ = 0, 1,2) and M^1 Ⅱ ( ν′ = 0) are reported.     

Theoretical study of spin-forbidden cooling transitions of indium hydride using ab initio methods

The feasibility of spin-forbidden cooling of the In H molecule is investigated based on ab initio quantum chemistry calculations. The potential energy curves for the X~1Σ_(0~+)~+, a~3Π_~(0~-), a~3Π_(0~+), a~3Π_1, a~3Π_2, A~1Π_1, 1~3Σ_(0~-)~+, and 1~3Σ_1~+states of In H are obtained based on multi-reference configuration interaction plus the Davidson corrections method. The calculated spectroscopic constants are in good agreement with the available experimental data. In addition, the influences of the active space and spin–orbit coupling effects on the potential energy curves and spectroscopic constants are also studied. For Re of a~3Π_(0~-), a~3Π_(0~+), a~3Π_1, and a~3Π_2 states, the error from large active space is small. The potential energy curve of the A~1Π_1state is not smooth for small active space. The spin–orbit coupling effects have great influences on the potential well depth and equilibrium internuclear distance of the A~1Π state. The Franck–Condon factors and radiative lifetimes are obtained on the basis of the transition dipole moments of the a~3Π_(0~+) → X~1Σ_(0~+)~+, a~3Π_1 → X~1Σ_(0~+)~+, and A~1Π_1 → X~1Σ_(0~+)~+ transitions. Our calculation indicates that the a~3Π_1( ν'= 0) → X~1Σ_(0~+)~+(ν = 0) transition provides a highly diagonally distributed Franck–Condon factor and a short radiative lifetime for the a3Π1 state, which can ensure rapid and efficient laser cooling of In H.The proposed laser drives a~3Π_1 → X~1Σ_(0~+)~+ transitions by using three wavelengths.     

The characteristics of doubly and triply charged ions C2^2＋, C2^2- and C2^3＋

Based on group theory and atomic and molecular reaction statics, this paper derives the possible electronic states of C^{2+}_2, C^{2-}_2 and C^{3+}_2, and their reasonable dissociation limits and determines their ground electronic states C^{2+}_2(X^3Π_u), C^{2-}_2(X^1Σ^+_g) and C^{3+}_2(X^4Σ^-_u) using quantum mechanical calculations at the level of QCISD/6-311G^*. All the potential energy curves of their ground states have both a minimum and a maximum, which are the so-called "energy trapped" molecules. This sort of potential maximum is chiefly due to Coulomb repulsion. We propose the perturbation effect of ionic charges, which is used to explain why the orbital degeneracy of diatomic ions may be removed. The characteristics of potential curves for diatomic ions are briefly described.     

Raman紫外双共振研究C_2H_2分子的碰撞转动弛豫

本文利用受激Raman抽运,选择性地制备了C_2H_2分子电子基态的红外非激活振动能级的单一转动态(X~1∑~+,v″=1,J″=9,11,13),并从紫外激光诱导的A~1Au(v′=1)←X~1∑~+(v″=1)荧光谱,直接测定上述三个转动态的C_2H_2—C_2H_2碰撞的消激活速率常数,它们分别为(7.96±1.04)×10~(-10),(8.79±0.97)×10~(-10),(8.76±0.88)×10~(-10)cm~3~(-1),以及由这些初始转动态向其它不同转动态(v′=1,J′=1,3,5,7,9,11,13,15)多量子跃迁转移的激活速率常数。     

First-principles Study on the Magnetic,Half-metal and Thermoelectric Transport Properties of Inorganic-Organic Hybrid Compounds [C_4N_2H_(12)][Fe_4~Ⅱ(HPO_3)_2(C_2O_4)_3]

The electronic structure,magnetic and half-metal properties of inorganic-organic hybrid compound [C_4N_2H_(12)][Fe_4~Ⅱ(HPO_3)_2(C_2O_4)_3] are investigated by using the full-potential linearized augmented plane wave (FPLAPW) method within density-functional theory (DFT) calculations.The density of states (DOS),the total energy of the cell and the spontaneous magnetic moment of [C_4N_2H_(12)][Fe_4~Ⅱ(HPO_3)_2(C_2O_4)_3] are calculated.The calculation results reveal that the low-temperature phase of [C_4N_2H_(12)][Fe_4~Ⅱ(HPO_3)_2(C_2O_4)_3] exhibits a stable ferromagnetic (FM) ground state,and we find that this organic compound is a half-metal in FM state.In addition,we have calculated antiferromagnetically coupled interactions,revealing the existence of antiferromagnetic (AFM),which is in agreement with the experiment.We have also found that [C_4N_2H_(12)][Fe_4~Ⅱ(HPO_3)_2(C_2O_4)_3] is a semiconductor in the AFM state with a band gap of about 0.40 eV.Subsequently,the transport properties for potential thermoelectric applications have been studied in detail based on the Boltzmann transport theory.     

用耦合簇理论及相关一致五重基研究H2S(C2v,X1A′)的解析势函数

运用CCSD(T)理论和相关一致五重基对基态H2S分子进行了结构优化以及离解能和频率的计算.得到的结果是:该分子的基态为C2v结构,平衡核间距RS-H =0.13374 nm,键角∠HSH=92.3837°,离解能D0(H-SH)=3.8999 eV,频率υ1(a1)=1121.1865 cm-1,υ2(a1)=2727.5121 cm-1,υ3(a1)=2742.8342 cm-1.这些结果与实验结果均较为相符.对H2(X1Σ+g)分子使用cc-pV6Z、对SH(X2Π)自由基使用aug-cc-pV5Z基组进行几何优化和谐振频率的计算并进行单点能扫描,且将单点能扫描结果拟合成了解析的Murrell-Sorbie函数.与实验结果及其它理论结果的比较表明,本文关于SH(X2Π)自由基光谱常数(De,Re,ωe,Be,αe和ωeχe)的计算结果达到了较高的精度.采用多体项展式理论导出了H2S(C2v,X1A′)分子的解析势能函数,其等值势能图准确再现了该分子的离解能和平衡结构特征.报导了H2S(C2v,X1A′)分子对称伸缩振动等值势能图中存在的两个对称鞍点,对应于反应SH+H→SH2,势垒高度为0.1680×4.184 kJ/mol.     

Resonant nuclear reaction ~(23)Mg(p,γ) ~(24)Al in strongly screening magnetized neutron star crust

Based on the relativistic theory of superstrong magnetic fields(SMF), by using three models those of Lai(LD), Fushiki(FGP), and our own(LJ), we investigate the influence of SMFs due to strong electron screening(SES) on the nuclear reaction ~(23)Mg(p,γ) ~(24)Al in magnetars. In a relatively low density environment(e.g., ρ_7 0.01)and 1 B_(12) 10~2, our screening rates are in good agreement with those of LD and FGP. However, in relatively high magnetic fields(e.g., B_(12) 10~2), our reaction rates can be 1.58 times and about three orders of magnitude larger than those of FGP and LD, respectively(B_(12), ρ~7 are in units of 10~(12)G, 10~7 g cm~(-3)). The significant increase of strong screening rate can imply that more ~(23)Mg will escape from the Ne-Na cycle due to SES in a SMF. As a consequence,the next reaction, ~(24)Al(+β, ν) ~(24)Mg, will produce more ~(24)Mg to participate in the Mg-Al cycle. Thus, it may lead to synthesis of a large amount of A20 nuclides in magnetars.     

CdH分子基态X~2∑~+和激发态A~2П光谱和寿命测量

采用一束激光为泵浦光另一束激光为探测光的方法,获得CdH分子A~2Π态和X~2∑~+态之间跃迁产生的具有转动结构的多个荧光谱和激发谱带.对荧光的时间分辨研究,给出A~2Π态寿命τ_0=59.5±2.3ns,对A~2Π(v=0)态Cd原子的碰撞猝灭截面为(1.31±0.03)×10~(-15)cm~2;X~2∑~+态寿命τ_0=61.0±4.6μs,引起X~2∑~+(v=0)态寿命衰减的碰撞截面为(1.1±0.1)×10~(-18)cm~2.     

Transition Dipole Moment Measurements of Ultracold Photoassociated ~(85)Rb~(133)Cs Molecules by Depletion Spectroscopy

The transition dipole moments(TDMs) of ultracold85 Rb133 Cs molecules between the lowest vibrational ground level, (X~1Σ~+( v= 0, J= 1), and the two excited rovibrational levels, 2~3Π_0+(v′= 10, J′= 2) and 2~1Π_1(v′= 22,J′= 2), are measured using depletion spectroscopy. The ground-state85 Rb133 Cs molecules are formed from cold mixed component atoms via the 2~3Π_0-( v= 11, J= 0) short-range level, then detected by time-of-flight mass spectrum. A home-made external-cavity diode laser is used as the depletion laser to couple the ground level and the two excited levels. Based on the depletion spectroscopy, the corresponding TDMs are then derived to be 3.5(2)×10~(-3)eα_α and 1.6(1)×10~(-2)eα_α, respectively, where 0)(60 represents the atomic unit of electric dipole moment. The enhance of TDM with nearly a factor of 5 for the 21Π1(v′= 22, J′= 2) excited level means that it has stronger coupling with the ground level. It is meaningful to find more levels with much more strong coupling strength by the represented depletion spectroscopy to realize direct stimulated Raman adiabatic passage transfer from scattering atomic states to deeply molecular states.     

Measurements of differential and angle-integrated cross sections for the ~(10)B(n, α)~7Li reaction in the neutron energy range from 1.0 eV to 2.5 MeV

Differential and angle-integrated cross sections for the ~(10)B(n,α)~7 Li,~(10)B(n,α_0) ~7 Li and ~(10)B(n,α_1) ~7 Li~*reactions have been measured at CSNS Back-n white neutron source.Two enriched(90%) ~(10)B samples 5.0 cm in diameter and～85.0 μg/cm~2 in thickness each with an aluminum backing were prepared,and back-to-back mounted at the sample holder.The charged particles were detected using the silicon-detector array of the Light-charged Particle Detector Array(LPDA) system.The neutron energy En was determined by TOF(time-of-flight) method,and the valid a events were extracted from the E_n-Amplitude two-dimensional spectrum.With 15 silicon detectors,the differential cross sections of a-particles were measured from 19.2°to 160.8°.Fitted with the Legendre polynomial series,the(n,a) cross sections were obtained through integration.The absolute cross sections were normalized using the standard cross sections of the ~(10)B(n,α) ~7 Li reaction in the 0.3-0.5 MeV neutron energy region.The measurement neutron energy range for the ~(10)B(n,α) ~7 Li reaction is 1.0 eV≤E_n 2.5 Me V(67 energy points),and that for the ~(10)B(n,α_0) ~7 Li and~(10)B(n,α_1) ~7 Li~*reactions is 1.0 eV≤E_n1.0 MeV(59 energy points).The present results have been analyzed by the resonance reaction mechanism and the level structure of the ~(11)B compound system,and compared with existing measurements and evaluations.     

New physics and two boosted W-jets plus missing energy

We show that the signature of two boosted W-jets plus substantial missing energy is very promising for probing heavy charged resonances(X~±) through the process of pp→X~+X~-→W~+W~-X~0 X~0,where X~0 denotes the dark matter candidate.The hadronic decay mode of the W boson is considered to maximize the number of signal events.When the mass split between X~± and X~0 is large,the jet-substructure technique must be utilized to analyze the boosted W-jet.Here,we consider the process of chargino pair production at the LHC,i.e.,pp→χ_1~+χ_1~-→W~+W~-χ_1~0χ_1~0,and demonstrate that the proposed signature is able to cover more parameter space of m_(χ_1~±) and m_(χ_1~0),than the conventional signature of multiple leptons plus missing energy.More importantly,the signature of interest is not sensitive to the spin of heavy resonances.     

Theoretical study of structure and analytic potential energy function for the ground state of PO2 molecule

In this paper, the energy, the equilibrium geometry, and the harmonic frequency of the ground electronic state of PO₂ are computed using B3LYP, B3P86, CCSD(T), and QCISD(T) methods in conjunction with 6-311++G(3df, 3pd) and cc-pVTZ basis sets. A comparison between the computational results and the experimental values indicates that the B3P86/6-311++G(3df, 3pd) method can give better energy calculation results for the PO₂ molecule. It is shown that the ground state of the PO₂ molecule has C_2v symmetry and its ground electronic state is X²A₁. The equilibrium parameters of the structure are R_P-O=0.1465 nm, d=19.218 eV. The bent vibrational frequency ν₁=386 cm^-1, the symmetric stretching frequency ν₂=1095 cm^-1, and the asymmetric stretching frequency ν₃=1333 cm^-1 are obtained. On the basis of atomic and molecular reaction statics, the reasonable dissociation limit for the ground state of the PO₂ molecule is determined. Then the analytic potential energy function of the PO₂ molecule is first derived by using the many-body expansion theory. The potential curves correctly reproduce the configurations and the dissociation energy for the PO₂ molecule.     

用耦合簇方法及相关一致基研究PH2(X2B1)自由基的解析势能函数

利用耦合簇方法和Dunning等提出的系列相关一致基对PH2自由基的基态结构进行优化,并使用优选出的cc-pV5Z基组对其进行频率计算.结果表明,平衡核间距RP-H=0.14185 nm,键角αHPH=91.8624°,离解能De(HP-H)=3.483 eV,对称伸缩振动频率ν1(a1)=2399.9781cm-1,弯曲振动频率ν2(a1)=1128.4213 cm-1,反对称伸缩振动频率ν3(b2)=2407.8374 cm-1.在此基础上采用多体项展式理论导出了PH2自由基的解析势能函数,其等值势能图准确再现了PH2自由基分子的平衡结构特征和动力学特征.     

Theoretical study of the structure and analytic potential energy function for the ground state of the PO₂ molecule

In this paper, the energy, equilibrium geometry, and harmonic frequency of the ground electronic state of PO2 are computed using the B3LYP, B3P86, CCSD(T), and QCISD(T) methods in conjunction with the 6-311++G(3df, 3pd) and cc-pVTZ basis sets. A comparison between the computational results and the experimental values indicates that the B3P86/6-311++G(3df, 3pd) method can give better energy calculation results for the PO 2 molecule. It is shown that the ground state of the PO2 molecule has C2v symmetry and its ground electronic state is X2 A1 . The equilibrium parameters of the structure are R P O = 0.1465 nm, ∠OPO = 134.96°, and the dissociation energy is Ed = 19.218 eV. The bent vibrational frequency ν 1 = 386 cm-1 , symmetric stretching frequency ν 2 = 1095 cm-1 , and asymmetric stretching frequency ν 3 = 1333 cm-1 are obtained. On the basis of atomic and molecular reaction statics, a reasonable dissociation limit for the ground state of the PO2 molecule is determined. Then the analytic potential energy function of the PO2 molecule is derived using many-body expansion theory. The potential curves correctly reproduce the configurations and the dissociation energy for the PO2 molecule.     

Theoretical study of the structure and analytic potential energy function for the ground state of the PO2 molecule

In this paper, the energy, equilibrium geometry, and harmonic frequency of the ground electronic state of PO2 are computed using the B3LYP, B3P86, CCSD（T）, and QCISD（T） methods in conjunction with the 6-311＋＋G（3df, 3pd） and cc-pVTZ basis sets. A comparison between the computational results and the experimental values indicates that the B3P86/6-311＋＋G（3df, 3pd） method can give better energy calculation results for the PO2 molecule. It is shown that the ground state of the PO2 molecule has C2v symmetry and its ground electronic state is X2A1. The equilibrium parameters of the structure are Rp-o = 0.1465 am, ZOPO = 134.96°, and the dissociation energy is Ed = 19.218 eV. The bent vibrational frequency Ul = 386 cm-1, symmetric stretching frequency v2 = 1095 cm-1, and asymmetric stretching frequency ua = 1333 em-1 are obtained. On the basis of atomic and molecular reaction statics, a reasonable dissociation limit for the ground state of the PO2 molecule is determined. Then the analytic potential energy function of the PO2 molecule is derived using many-body expansion theory. The potential curves correctly reproduce the configurations and the dissociation energy for the PO2 molecule.