Analysis of vibrational spectra of nano-bio molecules： Application to metalloporphrins

In this paper, we have applied the Lie algebraic model to nano-bio molecules to determine the vibrational spectra of different stretching and bending vibrational modes. The determined vibrational energy levels by the Lie algebraic model are compared with the experimental data. The results from the theoretical mode[ are consistent with the experimental data. The vibrational energy levels are clustering in the excited states.     

用代数哈米顿量研究CH3C1分子的振动谱

我们提出一种描述XH3分子的伸缩和弯曲振动的U(2)代数哈米顿量,其中包括了伸缩和弯曲振动的费米共振耦合;用它来拟合CH3Cl分子的实验数据,结果表明有较少参数的代数模型算得的偏差比其它模型算得的偏差要小.     

用代数哈米顿量研究CH_3Cl分子的振动谱(英文)

我们提出一种描述XH3分子的伸缩和弯曲振动的U(2)代数哈米顿量,其中包括了伸缩和弯曲振动的费米共振耦合,用它来拟合CH3Cl分子的实验数据,结果表明有较少参数的代数模型算得的偏差比其它模型算得的偏差要小.     

Accurate studies on the full vibrational energy spectra and molecular dissociation energies for some electronic states of N<Subscript>2</Subscript> molecule

It is usually very difficult to directly obtain molecular dissociation energy D _e and all accurate high-lying vibrational energies for most diatomic electronic states using modern experimental techniques or quantum theories, and it, is also very difficult to give accurate analytical expression for diatomic molecular dissociation energy. This study proposes a new analytical formula for obtaining accurate molecular dissociation energy based on the LeRoy and Bernstein’s energy expression in dissociation limit. A set of full vibrational energy spectra for some electronic states of N₂ molecule are studied using the algebraic method (AM) suggested recently, and the corresponding accurate molecular dissociation energies are evaluated using the proposed new formula and high-lying AM vibrational energies. The results show that the AM spectra and the new theoretical dissociation energies agree excellently with experimental data, and thereby providing a new physical approach to generating accurate dissociation energies for electronic states of diatomic molecules.     

分子部分电子态的高阶振动能级和离解能的精确研究

鉴于K₂分子电子态的振动能谱和分子离解能D_e在实际研究和应用中的重要性,应用Sun,Ren等人提出的基于微扰理论的代数方法(AM)和基于AM的代数能量方法(AEM)研究了K₂分子的X¹Σ⁺_g,a³Σ⁺_u,0^-_g,B¹Π_{u< 关键词： 2}分子')" href="#">K₂分子 代数方法 高阶振动能级 离解能     

Fermi Resonances and Vibrational Spectrum of a Polyatomic Molecule XY4: an Algebraic Approach

A U(2) algebraic model is introduced for the spectrum of a molecule XY₄, where the interactions between the stretch and bend modes are described by T_d symmetric Fermi resonance terms. The presented algebraic model in a limit corresponds to another model in recent literature. The vibrational spectrum of methane (CH₄) measured recently with modern spectroscopy techniques is employed to test those models. The obtained standard deviation between the observed and the calculated vibrational energy levels in the algebraic model is smaller than that in the corresponding model.     

Li_2部分电子态的完全振动能谱与离解能的精确研究

本文将孙卫国等建立的精确计算双原子分子离解能的解析表达式作为分子振动能级正确收敛的重要物理判据,应用代数方法,进一步研究了重要的碱金属Li2的5个电子态的完全振动能谱和离解能,获得了这些电子态的精确振动光谱常数,同时也得到了包括接近分子离解极限在内的完全振动能谱和与实验值符合得很好的理论离解能.这些计算结果为许多需要这些电子态振动数据的研究领域提供了重要的研究数据.     

双原子离子振动光谱与离解能的研究

结合代数方法(AM)和最近建立的计算精确的分子离解能的新解析表达式,进一步研究了部分双原子离子电子态的完全振动能谱和离解能,获得了与实验值符合得非常好的理论结果.研究结果表明,AM方法和新解析式相结合的理论方法同样也适用于双原子离子体系,该方法在理论上提供了获得双原子离子精确的振动光谱和离解能的物理新方法.     

代数方法计算正四面体分子伸缩振动能谱

用推广的U(2)代数模型,对正四面体分子的伸缩振动能谱进行了理 论研 究,该模型成功地应用到SnD4的最新观测到的高分辨能谱数据,所得计算值与实验值的标 准偏差是0.124 cm-1。     

碱金属氢化物双原子分子部分电子态的完全振动能谱和分子离解能的精确研究

应用作者建立的基于微扰理论能级表达式的代数方法，研究了碱金属氢化物双原子分子⁶LiH，⁷LiH，NaH，KH，RbH和CsH的A¹Σ⁺电子态的完全振动能谱{E_υ}，并应用基于代数方法的代数能量方法分别研究了以上各分子电子态的离解能.得到了这些电子态的精确的振动光谱常数和包括接近分子离解极限在内的完全振动能谱以及正确的理论离解能，从而为许多需要这些双原子分子的精确振动光谱的科学研究提供了必要的数据. 关键词： 碱金属氢化物 代数方法 振动能级 离解能     

Accurate vibrational energy spectra and dissociation energies of some diatomic electronic states

An algebraic method (AM) used to study the full vibrational spectra of diatomic systems, and an analytical formula used to calculate accurate molecular dissociation energies are applied to study the full vibrational spectra and molecular dissociation energies of some electronic states of homonuclear and heteronuclear diatomic molecules and diatomic ions. Studies show that the AM method and the analytical expression are reliable and economical physical methods for studying full vibrational spectra and molecular dissociation energies of diatomic electronic systems theoretically. They are particularly useful for those diatomic systems whose high-lying vibrational energies may not be available.      

Vibrational spectra of nickel metalloporphyrins: An algebraic approach

One of the most interesting areas of current research in molecular physics is the study of the vibrationally excitated states of medium and large molecules. In view of the considerable amount of experimental activity in this area, one needs theoretical models within which to interpret experimental data. Using Lie algebraic method, the vibrational energy levels of nickel metalloporphyrins like Ni(OEP), Ni porphyrin and Ni(TPP) are calculated for 16 vibrational modes. The algebraic Hamiltonian

Vibrational spectroscopy of Cm–H,C β –C β stretching vibrations of Nickel metalloporphyrins: An algebraic approach

An algebraic model of coupled anharmonic oscillators is introduced, capable of describing the stretching vibrations of medium and large polyatomic molecules. This model is applied to the calculation of C_m–H and C _β –C _β vibrational modes of nickel octaethyl porphyrins and nickel porphyrins molecules. The model appears to describe the data accurately.     

Accurate studies of dissociation energies and vibrational energies on alkali metals

This paper studies full vibrational spectra {Ev} and molecular dissociation energies De by using conventional least-squares （LS） fitting and an algebraic method （AM） proposed recently for 10 diatomic electronic states of ^7Li2, Na2, NaK and NaLi molecules based on some known experimental vibrational energies in a subset [Ev^expt] respectively. Studies show that： （1） although both the full AM spectrum {Ev^AM} and the LS spectrum {Ev^LS} can reproduce the known experimental energies in [Ev^expt], the {EAM} is superior to the {Ev^LS} in that the high-lying AM vibrational energies which may not be available experimentally have better or much better accuracy than those LS counterparts in {Ev^LS}, and so is the AM dissociation energy De^AM; （2） the main source of the errors in the data obtained by using the LS fitting is that the fitting which is just a pure mathematical process does not use any physical criteria that must be satisfied by the full vibrational spectrum, while the AM method does. This study suggests that when fitting or solving a physical equation using a set of source data, it is important not only to apply a proper mathematical tool, but also to use correct physical criteria which measure the physical properties of the data, kick out those data having bigger errors, and impose conditional convergence on the numerical process.     

理论离实验有多远?——用代数方法精确研究双原子分子的完全振动能谱和离解能

本文较系统地简介了双原子分子振动能谱和离解能的研究历史、现状及若干研究方法,重点介绍了孙卫国等最近建立的研究双原子分子完全振动能谱的代数方法(AM)和计算双原子分子离解能的新物理公式。然后应用AM方法和离解能新公式对一批同核和异核双原子分子,以及双原子分子离子电子态的完全振动能谱和离解能进行了研究。结果表明,AM方法和新建立的离解能解析式相结合的理论方法对研究双原子分子及离子的完全振动能谱和离解能是行之有效的、简单经济的物理方法,为实验技术难以精确测量其高激发振动能级或离解能的双原子分子或离子体系提供了获得精确的完全振动能谱和体系离解能的一种理论新方法。     

Calculation of Vibrations of Phenyldichloroarsine and Phenyldichlorophosphine and Analysis of Their Structure Parameters

The vibrational spectra of free molecules and aqueous solutions of phenyldichloroarsine and phenyldichlorophosphine have been analyzed by ab initio methods. Characteristic spectral parameters of these compounds, which can be used for monitoring the environment, have been revealed.     

Meta - Aminobenzoic Acid: Structures and Spectral Characteristics

Two conformations of minimum energy (I-syn and I-anti) were found in meta-aminobenzoic acid by the AMI semiempirical method. All the geometric parameters were optimized and compared with published data obtained by means of X-ray diffraction. The dipolar form of meta-aminobenzoic acid was also optimized by AM1. The vibrational spectra were computed in all cases. Several scale coefficients were used to improve the theoretical spectra. The total atomic charges, the electronic density and several thermodynamics parameters were also calculated.     

Studies on the full vibrational energy spectra for some electronic states of diatomic molecular ions XY+

The first accurate studies on the vibrational spectroscopic constants and the corresponding full vibrational energy spectra of some electronic states of diatomic molecular ions XY⁺ were performed using algebraic method(AM). The AM is applied on the X¹Σ⁺ state of BeH⁺, the X²Σ⁺ state of CO⁺, the X²Π_g state of F ₂ ⁺ , the A²Π_u state of O ₂ ⁺ and the X²Σ _g ⁺ state of Li ₂ ⁺ . The results show that AM can generate accurate vibrational spectroscopic constants as well as accurate full vibrational energy spectra by using some accurate experimental vibrational energies, and that the AM vibrational energies are better than other theoretical data. __________ Translated from Chinese Journal of Atomic and Molecular Physics, 2005, 22 (4) (in Chinese)     

Accurate studies on the full vibrational energy spectra and molecular dissociation energies for some electronic states of N_2 molecule

1 IntroductionAccurate results of high-lying vibrational energies and molecular dissociation energy De of diatomic electronic states are very important for thermodynamics, molecular spec- troscopy, reactive scatterings, and the collision physics of ultracold atoms. For example, the binding energy of the highest bound vibrational state to the ground vibrational state determines the s-wave scattering length. This in turn determines the low- energy (pre- dominantly s-wave) atomic elastic-scatteri…     

Decoupling multimode vibrational relaxations in multi-component gas mixtures: Analysis of sound relaxational absorption spectra

Decoupling the complicated vibrational-vibrational (V-V) coupling of a multimode vibrational relaxation remains a challenge for analyzing the sound relaxational absorption in multi-component gas mixtures. In our previous work [Acta Phys. Sin. 61 174301 (2012)], an analytical model to predict the sound absorption from vibrational relaxation in a gas medium is proposed. In this paper, we develop the model to decouple the V-V coupled energy to each vibrational- translational deexcitation path, and analyze how the multimode relaxations form the peaks of sound absorption spectra in gas mixtures. We prove that a multimode relaxation is the sum of its decoupled single-relaxation processes, and only the decoupled process with a significant isochoric-molar-heat can be observed as an absorption peak. The decoupling model clarifies the essential processes behind the peaks in spectra arising from the multimode relaxations in multi-component gas mixtures. The simulation validates the proposed decoupling model.