scholarly journals Spectroscopic Studies of Distorted Structure Systems in the Vibron Model: Application to Porphyrin and Its Isotopomers

2011 ◽  
Vol 2011 ◽  
pp. 1-5
Author(s):  
Srinivasa Rao Karumuri ◽  
Vijayasakhar Jallaparthi ◽  
Sreeram Venigalla
Keyword(s):  
Experimental Data ◽  
Vibrational Spectra ◽  
Good Accuracy ◽  
Energy Levels ◽  
Vibrational Analysis ◽  
Spectroscopic Studies ◽  
Algebraic Model ◽  
Model Application ◽  
Distorted Structure ◽  
Algebraic Technique

We have introduced an algebraic technique to biomolecules (porphyrins) family to determine the vibrational spectra. We present an algebraic model of vibrations of polyatomic biomolecules, as an example, the vibrational analysis of stretching modes of nickel octaetheylporphyrin (Ni(OEP)) and its isotopomers. The algebraic technique obtained the results are compared with experimental data; the results are showing good accuracy. Some reassignments of energy levels that predict location of energy states not yet observed.

scholarly journals Spectroscopic Studies on Distorted Structure Nanomolecules by Using Lie Algebraic Model

2012 ◽  
Vol 122 (1) ◽  
pp. 49-52
Author(s):  
S. Rao Karumuri ◽  
K. Girija Sravani ◽  
J. Vijayshekar ◽  
L.S.S. Reddy
Keyword(s):  
Spectroscopic Studies ◽  
Algebraic Model ◽  
Distorted Structure

Algebraic study of vibrational spectra of the tetra-atomic molecules N15C12C12N15 and N14C13C13N14

2016 ◽  
Vol 15 (04) ◽  
pp. 1650036 ◽  
Author(s):  
Kamal Ziadi ◽  
Abdelhamid Bouldjedri
Keyword(s):  
Experimental Data ◽  
Potential Energy ◽  
Energy Levels ◽  
Algebraic Approach ◽  
Potential Energy Function ◽  
Vibration Modes ◽  
Bending Vibration ◽  
Dissociation Energies ◽  
Algebraic Technique ◽  
Good Agreement

In this paper, an accurate and efficient algebraic technique is used to compute linear tetra-atomic molecules stretching and bending vibration modes. Namely, several collective energy levels of linear XYYX molecules N[Formula: see text]C[Formula: see text]C[Formula: see text]N[Formula: see text] and N[Formula: see text]C[Formula: see text]C[Formula: see text]N[Formula: see text] have been described in the framework of the algebraic approach based on U[Formula: see text] Lie algebra. The results are compared to experimental data, good agreement has been obtained. The potential energy function of the two molecules is analyzed and the dissociation energies are derived.

Energy Levels and Electromagnetic Transition of 90-94mo Nuclei Using Ibm-1

2020 ◽  
pp. 149-152
Keyword(s):  
Experimental Data ◽  
Transition Probability ◽  
Energy Levels ◽  
Dynamical Symmetry ◽  
Interacting Boson Model ◽  
Excitation Energies ◽  
Electromagnetic Transition ◽  
Boson Model ◽  
Energy States ◽  
Good Agreement

The energy states for the J , b , ɤ bands and electromagnetic transitions B (E2) values for even – even molybdenum 90 – 94 Mo nuclei are calculated in the present work of "the interacting boson model (IBM-1)" . The parameters of the equation of IBM-1 Hamiltonian are determined which yield the best excellent suit the experimental energy states . The positive parity of energy states are obtained by using IBS1. for program for even 90 – 94 Mo isotopes with bosons number 5 , 4 and 5 respectively. The" reduced transition probability B(E2)" of these neuclei are calculated and compared with the experimental data . The ratio of the excitation energies of the 41+ to 21+ states ( R4/2) are also calculated . The calculated and experimental (R4/2) values showed that the 90 – 94 Mo nuclei have the vibrational dynamical symmetry U(5). Good agreement was found from comparison between the calculated energy states and electric quadruple probabilities B(E2) transition of the 90–94Mo isotopes with the experimental data .

Comparison of the Conformational Stability for Several Vinylhalomethanes and Silanes with Experiment Using MP2 Perturbation Theory and DFT

2007 ◽  
Vol 72 (1) ◽  
pp. 15-50 ◽  
Author(s):  
Wolfgang Förner ◽  
Hassan M. Badawi
Keyword(s):  
Experimental Data ◽  
Vibrational Spectra ◽  
Recent Literature ◽  
Conformational Stability ◽  
Basis Set ◽  
Major Conclusion ◽  
Stable Conformer ◽  
Polarization Functions ◽  
Complete Series ◽  
Triple Zeta

In recent literature it was reported that the valence triple zeta basis set augmented by polarization functions is not too reliable for vinyl monohalo- and dihalomethanes and -silanes, the halogen being fluorine and chlorine. The major conclusion was that a valence triple zeta basis is too small to be augmented by polarization functions in a balanced way, at least on vinylmonofluoromethane. Thus we decided to apply the 6-311++G** basis set to the complete series of methanes, silanes and germanes (the latter ones are just added for completeness because no experimental data are available for them and, moreover, we published them already previously) and to compare the results to experimental data available in the literature to see whether the failures of this basis set show up in the complete series of molecules. In the literature we found five such molecules and the information which of the conformers is the most stable. Indeed we found that predictions on the relative stability of conformers in those systems with this basis set and MP2 as well as DFT are with a 60:40 chance, three being correct predictions and two being incorrect ones out of the five. However, since the energy differences are rather small in these systems and due to the fact that - as a consequence of twofold degeneracy of the gauche conformer on the potential curve of the torsional vibration - the abundances of the conformers in equilibrium do not change too much, we decided to calculate also vibrational spectra for three examples and to compare them also to experiment. It is reported that besides the failures in total energy (we have chosen two examples where predictions of the nature of the stable conformer are correct, and one where it is not), the vibrational spectra are rather well reproduced, especially when experimental energies are used to calculate abundances in equilibrium in the case where the prediction of the stable conformer failed.

scholarly journals Electronic Structure of Two New Bis-Schiff Base Ligands using DFT Method

2021 ◽  
pp. 10-15
Author(s):  
Elham Abdalrahem Bin Selim ◽  
Mohammed Hadi Al–Douh ◽  
Hassan Hadi Abdullah ◽  
Dahab Salim Al–Nohey
Keyword(s):  
Experimental Data ◽  
Biological Activity ◽  
Metal Ion ◽  
Energy Levels ◽  
Dft Method ◽  
Ftir Spectra ◽  
Schiff Base Ligands ◽  
Lumo Energy ◽  
Homo Lumo ◽  
Good Agreement

Two bis-Schiff Bases 1 and 2 are ligands that can coordinate with manganese metal to form stable complexes and have biological activity. Thermodynamic parameters, HOMO-LUMO energy levels and FTIR spectra of two ligands have been computed using B3LYP/6-311++G(d,p) functional of the DFT calculations. Both ligands are favored thermodynamically, and the ligand 1 has been shown to be more stable than ligand 2. The Polarizability values of two ligands have been investigated. The results refer that ligand 2 interacts earlier than ligand 1 to the metal ion. The FTIR spectra of two ligands have been evaluated. All results show the good agreement between the theoretical and experimental data.

scholarly journals SOLVING INVERSE PROBLEM OF CHEMICAL KINETICS WITH USE OF CUBIC SPLINES

2020 ◽  
Vol 63 (7) ◽  
pp. 61-66
Author(s):  
Nikolay I. Kol'tsov
Keyword(s):  
Experimental Data ◽  
Inverse Problem ◽  
Chemical Kinetics ◽  
Good Accuracy ◽  
Cubic Splines ◽  
Rate Of Change ◽  
Reference Points ◽  
Additional Advantage ◽  
Instantaneous Rate ◽  
Relaxation Curves

A simple effective method for solving the inverse problem of chemical kinetics based on non-stationary experiments for multistage reactions occurring in an isothermal reactor of ideal mixing is described. The idea of the method is based on taking into account the distinctive features (informativeness) of different fragments of relaxation curves for chemical reactions with arbitrary (non-monotonic) kinetics and their as accurate approximation as possible. For this purpose, non-linear (cubic) splines are used to describe different informative fragments of relaxation curves, which allow to approximate and interpolate experimental data as accurately as possible. An additional advantage of cubic splines, from the point of view of the implementation of the described method, is their continuity at all given points up to and including second-order derivatives (smoothness). This allows us to calculate with good accuracy not only the concentration of reagents, but also the instantaneous rate of change at any time. The consequence of this is the possibility of a sufficiently accurate solution of the inverse problem based on the data of non-stationary experiments. The correctness of the mathematical model used and the stability of the method were tested using variations of the original data. An example of using the method for determining the intervals of physical values of the rate constants of the stages of a two-stage reaction is given. The influence of the method of selecting the reference points (structure) of the spline and measurement errors (noise) of experimental data on the error of determining the speed constants of the stages is estimated. The efficiency of application and good accuracy of the method for solving the inverse problem of chemical kinetics of multistage reactions occurring in non-gradient systems with taking into account of noise is shown.

scholarly journals DEVELOPMENT AND TESTING OF ALGORITHM FOR CALCULATION OF OPERATING PARAMETERS OF TRAWLING SYSTEMS

2019 ◽  
Vol 198 ◽  
pp. 221-229 ◽  
Author(s):  
E. A. Zakharov ◽  
O. N. Kruchinin ◽  
D. L. Shabelsky
Keyword(s):  
Experimental Data ◽  
Visual Basic ◽  
Educational Process ◽  
Resistance Force ◽  
Operating Parameters ◽  
Calculation Algorithm ◽  
Model Application ◽  
Bottom Trawling ◽  
Good Convergence ◽  
Expansion Force

Numerical model of trawling system is developed on the base of equilibrium principle, using F.I. Baranov’s scheme of its power and geometric parameters interdependence. The model application to bottom trawling takes into account the effect of bottom grounds on the resistance force and expansion force of the trawling system. Algorithm is proposed for calculation of operating parameters of bottom and midwater trawls, with an operation to minimize the error of iteration. The model and the calculation algorithm were tested in MS Office Excel environment, using Visual Basic programming, and showed good convergence of the calculated and experimental data that indicates reliability of the model. This algorithm and the program for calculation of operating parameters could be used for trawl designing, in accounting surveys to determine the trawl opening, and in educational process for training the industrial fishery scholars.

RELATIVISTIC ENERGY, OSCILLATOR STRENGTHS AND TRANSITION RATES OF THE 1s2 2 ln l 1S(m)(n =2–6, m1–5) STATES FOR Be-LIKE SYSTEM

2005 ◽  
Vol 16 (06) ◽  
pp. 951-968 ◽  
Author(s):  
MENG ZHANG ◽  
BING-CONG GOU
Keyword(s):  
Experimental Data ◽  
Energy Levels ◽  
Oscillator Strengths ◽  
Relativistic Energy ◽  
Transition Rates ◽  
Isoelectronic Sequence ◽  
Polarization Effects ◽  
First Order ◽  
Variational Calculations ◽  
First Order Perturbation

Variational calculations are carried out with a multiconfiguration-interaction wave function to obtain the relativistic energies of the 1s2 2 ln l 1 S (m)(n =2–6, m1–5) states for the beryllium isoelectronic sequence (Z =4–10). Relativistic corrections and the mass polarization effects are evaluated with the first-order perturbation theory. The identifications of the energy levels for 1s2 2 ln l 1 S (m)(n =2–6, m1–5) states in the Be-like ions are reported. The oscillator strengths, transition rates and wavelengths are also calculated. The calculated results are compared with other theoretical and experimental data in the literature.

Energy Levels of 50Ca Nucleus as a Function of the Classical Coupling Angle within MSDI

2021 ◽  
Vol 19 (5) ◽  
pp. 61-67
Author(s):  
Ali Khalaf Hasan ◽  
Dalal Naji Hameed
Keyword(s):  
Experimental Data ◽  
Angular Momentum ◽  
Shell Model ◽  
Energy Levels ◽  
Model Space ◽  
Closed Shell ◽  
Excitation Energies ◽  
Modified Surface ◽  
Coupling Angle ◽  
Surface Delta Interaction

In the construction of this kind of shell model, we take the residual interaction to be modified surface delta interaction MSDI. We have studied the excitation energies of the 50Ca a nucleus, which contain two neutrons outside closed shell of the 48Ca. Neutrons are in the model space pfpg. The energy levels and angular momentum of all possible cases were investigated. Thereby, we have effectively utilized a theoretical process to find link among the traditional coupling angle and energy levels at different orbital within neutron - neutron interaction. We observe the energy stages appear to follow two overall functions which depend on the classical coupling angles but are unconstrained of angular momentum I. We find out that our results agree with the experimental data.

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