Science Publishing Group: International Journal of Computational and Theoretical Chemistry: Table of Contents
<i> International Journal of Computational and Theoretical Chemistry (IJCTC) </i>, a peer-reviewed open access journal published bimonthly in English-language, provides a broad coverage of developments in theoretical and computational chemistry, as well as their applications to other scientific fields. Articles are broadly categorized into quantum chemistry, chemical dynamics, statistical mechanics, and chemical biology, ranging from fundamental theoretical methodology and computational algorithm to numerical applications. It also seeks to provide theories that explain chemical observations. Major components include the application of quantum mechanics to the understanding of valency, molecular dynamics, statistical thermodynamics and theories of electrolyte solutions, reaction networks, polymerization and catalysis.
http://www.sciencepublishinggroup.com/j/ijctc Science Publishing Group: International Journal of Computational and Theoretical Chemistry: Table of Contents
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International Journal of Computational and Theoretical Chemistry
International Journal of Computational and Theoretical Chemistry
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Sadhana Polynomial and its Index of Hexagonal System Ba,b
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Let G be an arbitrary graph. Two edges e=uv and f=xy of G are called co-distant (briefly: e co f) if they obey the topologically parallel edges relation. The Sadhana polynomial Sd(G,x), for counting qoc strips in G was defined by Ashrafi and co-authors as Sd(G,x)= cm(G,c)xE(G)-C where m(G,c), being the number of qoc strips of length c. This polynomial is most important in some physico chemical structures of molecules. In this paper, we compute the Sadhana polynomial and its index of an important class of benzenoid system.
Let G be an arbitrary graph. Two edges e=uv and f=xy of G are called co-distant (briefly: e co f) if they obey the topologically parallel edges relation. The Sadhana polynomial Sd(G,x), for counting qoc strips in G was defined by Ashrafi and co-authors as Sd(G,x)= cm(G,c)xE(G)-C where m(G,c), being the number of qoc strips of length c. This polynomial is most important in some physico chemical structures of molecules. In this paper, we compute the Sadhana polynomial and its index of an important class of benzenoid system.
Sadhana Polynomial and its Index of Hexagonal System Ba,b
doi:10.11648/j.ijctc.20130102.11
International Journal of Computational and Theoretical Chemistry
2014-01-01
© Science Publishing Group
Mohammad Reza Farahani
Sadhana Polynomial and its Index of Hexagonal System Ba,b
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10
10
2014-01-01
2014-01-01
10.11648/j.ijctc.20130102.11
http://www.sciencepublishinggroup.com/journal/paperinfo.aspx?journalid=228&doi=10.11648/j.ijctc.20130102.11
© Science Publishing Group
A Study on Structural Aspects of Indoline-2, 3-Dione-3-Oxime: Experimental and Theoretical Approach
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Indoline-2,3-dione-3-oxime(IDOX) was synthesized and characterized by IR, mass and 1H-NMR. The HyperChem 7.5 software was used for quantum mechanical calculations. The geometry optimization was carried out using Ab Initio method. The theoretical spectral data and QSAR parameters were generated with semi empirical single point AM1 method. The HOMO and LUMO frontier orbital energies were also computed for the optimized keto and enol forms of IDOX molecule. The experimental and theoretical spectral data are nearly comparable. The pH- metry studies indicated presence of one dissociable proton in IDOX.
Indoline-2,3-dione-3-oxime(IDOX) was synthesized and characterized by IR, mass and 1H-NMR. The HyperChem 7.5 software was used for quantum mechanical calculations. The geometry optimization was carried out using Ab Initio method. The theoretical spectral data and QSAR parameters were generated with semi empirical single point AM1 method. The HOMO and LUMO frontier orbital energies were also computed for the optimized keto and enol forms of IDOX molecule. The experimental and theoretical spectral data are nearly comparable. The pH- metry studies indicated presence of one dissociable proton in IDOX.
A Study on Structural Aspects of Indoline-2, 3-Dione-3-Oxime: Experimental and Theoretical Approach
doi:10.11648/j.ijctc.20130102.12
International Journal of Computational and Theoretical Chemistry
2014-01-01
© Science Publishing Group
K. Laxmi
A Study on Structural Aspects of Indoline-2, 3-Dione-3-Oxime: Experimental and Theoretical Approach
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17
17
2014-01-01
2014-01-01
10.11648/j.ijctc.20130102.12
http://www.sciencepublishinggroup.com/journal/paperinfo.aspx?journalid=228&doi=10.11648/j.ijctc.20130102.12
© Science Publishing Group
Parametrically Temperature-Dependent Potential for Molecular Dynamics Simulation of Uranium Dioxide Properties
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The present paper justifies the application of the temperature-dependent potential to the molecular dynamics method through the example of uranium dioxide. Substantiation of the temperature dependence of interatomic potential is carried out based on the Newton quantum equation. Mean force can be represented as a sum of derivative of potential at the average atomic coordinate and the summand that depends on square dispersion of the coordinate depending on the temperature of the crystal. Temperature dependence of potential is introduced as linear slightly varying functions of the Coulomb plus Buckingham potential. The selection of parameters of potential was done at three temperature values: the initial temperature and temperatures of phase transitions – 2670 and 3120K, parameters of potentials for all other temperatures were found by approximation. We calculated temperature dependencies for the lattice constant, enthalpy, heat capacity under constant pressure and volume. Application of the temperature-dependent potential well complies with experimental data; the difference did not exceed 0.5% in the entire temperature range of 300-3120K.
The present paper justifies the application of the temperature-dependent potential to the molecular dynamics method through the example of uranium dioxide. Substantiation of the temperature dependence of interatomic potential is carried out based on the Newton quantum equation. Mean force can be represented as a sum of derivative of potential at the average atomic coordinate and the summand that depends on square dispersion of the coordinate depending on the temperature of the crystal. Temperature dependence of potential is introduced as linear slightly varying functions of the Coulomb plus Buckingham potential. The selection of parameters of potential was done at three temperature values: the initial temperature and temperatures of phase transitions – 2670 and 3120K, parameters of potentials for all other temperatures were found by approximation. We calculated temperature dependencies for the lattice constant, enthalpy, heat capacity under constant pressure and volume. Application of the temperature-dependent potential well complies with experimental data; the difference did not exceed 0.5% in the entire temperature range of 300-3120K.
Parametrically Temperature-Dependent Potential for Molecular Dynamics Simulation of Uranium Dioxide Properties
doi:10.11648/j.ijctc.20130103.11
International Journal of Computational and Theoretical Chemistry
2014-01-01
© Science Publishing Group
Nagornov Yuri
Katz Andrey
Parametrically Temperature-Dependent Potential for Molecular Dynamics Simulation of Uranium Dioxide Properties
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3
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26
2014-01-01
2014-01-01
10.11648/j.ijctc.20130103.11
http://www.sciencepublishinggroup.com/journal/paperinfo.aspx?journalid=228&doi=10.11648/j.ijctc.20130103.11
© Science Publishing Group
Teaching Chemistry through Music in Elementary Schools
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Atalay Mesfin. Chemistry to Music: Discovering how Music-Based Teaching Affects Academic Achievement and Student Motivation in an 8th Grade Science Class in Debremarkos Elementary school. Teachers should have access to new and innovative tools in order to engage and motivate their students in the classroom. This is especially important as many students view school as an antiquated and dull environment – which they must seemingly suffer through to advance. School need not be a dreaded environment. The use of music as a tool for learning can be employed by any teacher to create an engaging and exciting atmosphere whose students actively participate and learn to value their classroom experience. Through this study, product and process was developed that is now available for any 8th grade science teacher interested in using music to enhance their content. In this study 8th grade students (n=41) in public school classroom actively interacted with modern songs created to enhance the teaching of chemistry. Data were collected and analyzed in order to determine the effects that the music treatment had on student achievement and motivation, compared to a control group (n=35). Current literature provides a foundation for the benefits for music listening and training, but academic research in the area of using music as a tool for teaching content was noticeably absent. This study identifies a new area of research called “Music-based Teaching” which results in increases in motivation for 8th grade students learning chemistry. The unintended results of the study are additionally significant as the teacher conducting the treatment experienced newfound enthusiasm, passion, and excitement for his profession. Chemistry to Music: Discovering How Music-Based Teaching Affects Academic Achievement and Student Motivation in an 8th Grade Science Class in Debremarkos Elementary school.
Atalay Mesfin. Chemistry to Music: Discovering how Music-Based Teaching Affects Academic Achievement and Student Motivation in an 8th Grade Science Class in Debremarkos Elementary school. Teachers should have access to new and innovative tools in order to engage and motivate their students in the classroom. This is especially important as many students view school as an antiquated and dull environment – which they must seemingly suffer through to advance. School need not be a dreaded environment. The use of music as a tool for learning can be employed by any teacher to create an engaging and exciting atmosphere whose students actively participate and learn to value their classroom experience. Through this study, product and process was developed that is now available for any 8th grade science teacher interested in using music to enhance their content. In this study 8th grade students (n=41) in public school classroom actively interacted with modern songs created to enhance the teaching of chemistry. Data were collected and analyzed in order to determine the effects that the music treatment had on student achievement and motivation, compared to a control group (n=35). Current literature provides a foundation for the benefits for music listening and training, but academic research in the area of using music as a tool for teaching content was noticeably absent. This study identifies a new area of research called “Music-based Teaching” which results in increases in motivation for 8th grade students learning chemistry. The unintended results of the study are additionally significant as the teacher conducting the treatment experienced newfound enthusiasm, passion, and excitement for his profession. Chemistry to Music: Discovering How Music-Based Teaching Affects Academic Achievement and Student Motivation in an 8th Grade Science Class in Debremarkos Elementary school.
Teaching Chemistry through Music in Elementary Schools
doi:10.11648/j.ijctc.20140201.11
International Journal of Computational and Theoretical Chemistry
2014-01-01
© Science Publishing Group
Atalay Mesfin Anteneh
Teaching Chemistry through Music in Elementary Schools
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1
13
13
2014-01-01
2014-01-01
10.11648/j.ijctc.20140201.11
http://www.sciencepublishinggroup.com/journal/paperinfo.aspx?journalid=228&doi=10.11648/j.ijctc.20140201.11
© Science Publishing Group
Computational (DFT) Simulations for Comparative Prediction of Chemical Reactivity and Stability of Linoleic and Stearic Acid Molecules
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The frontier molecular orbitals (HOMO and LUMO) of stearic and linoleic acids were simulated using density functional theory (DFT) at the B3LYP/6-31G*basis set level with the use of Spartan ’10 wave function software with a view to comparing their reactivity and stability based on some theoretically calculated parameters. The total energy (absolute values), energy gap between the HOMO and LUMO, EHOMO, total energy and global hardness values of stearic acids were found to be higher than those of linoleic acid while values of ELUMO, dipole moment and global softness calculated were higher for linoleic acid than stearic acid. Results show that linoleic acid would have higher reactivity and lower stability than stearic acid due to its relative softness. Spectroscopic investigation gives similar spectral positions with an additional infra-red vibrational frequency at around 3000 cm-1 for linoleic acid.
The frontier molecular orbitals (HOMO and LUMO) of stearic and linoleic acids were simulated using density functional theory (DFT) at the B3LYP/6-31G*basis set level with the use of Spartan ’10 wave function software with a view to comparing their reactivity and stability based on some theoretically calculated parameters. The total energy (absolute values), energy gap between the HOMO and LUMO, EHOMO, total energy and global hardness values of stearic acids were found to be higher than those of linoleic acid while values of ELUMO, dipole moment and global softness calculated were higher for linoleic acid than stearic acid. Results show that linoleic acid would have higher reactivity and lower stability than stearic acid due to its relative softness. Spectroscopic investigation gives similar spectral positions with an additional infra-red vibrational frequency at around 3000 cm-1 for linoleic acid.
Computational (DFT) Simulations for Comparative Prediction of Chemical Reactivity and Stability of Linoleic and Stearic Acid Molecules
doi:10.11648/j.ijctc.20140202.11
International Journal of Computational and Theoretical Chemistry
2014-05-27
© Science Publishing Group
Ituen, E. B.
Asuquo, J. E.
Ogede, O. R.
Computational (DFT) Simulations for Comparative Prediction of Chemical Reactivity and Stability of Linoleic and Stearic Acid Molecules
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2
19
19
2014-05-27
2014-05-27
10.11648/j.ijctc.20140202.11
http://www.sciencepublishinggroup.com/journal/paperinfo.aspx?journalid=228&doi=10.11648/j.ijctc.20140202.11
© Science Publishing Group
QSAR for Antimycobacterial Activity of β-Thia Adduct of Chalcone and Diazachalcone Derivatives
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Quantitative structure-activity antimycobacterial relationships have been studied for a series of β-thia adduct of chalcone and diazachalcone derivatives by means of multiple linear regression (MLR) and artificial neural networks (ANN). The antimycobacterial activity against M. tuberculosis H37Rv of the compounds studied was well correlated with descriptors encoding the chemical structure. Using the pertinent descriptors revealed by a stepwise procedure in the multiple linear regression technique, a correlation coefficient of 0.9798 (s=0.0869) for the training set was obtained for the ANN model in a [3-3-1] configuration. The results show that the antimycobacterial activity of these compounds is strongly dependent on hydrogen-bonding donors, molecular refraction and also molecular connectivity indices for 2nd order.
Quantitative structure-activity antimycobacterial relationships have been studied for a series of β-thia adduct of chalcone and diazachalcone derivatives by means of multiple linear regression (MLR) and artificial neural networks (ANN). The antimycobacterial activity against M. tuberculosis H37Rv of the compounds studied was well correlated with descriptors encoding the chemical structure. Using the pertinent descriptors revealed by a stepwise procedure in the multiple linear regression technique, a correlation coefficient of 0.9798 (s=0.0869) for the training set was obtained for the ANN model in a [3-3-1] configuration. The results show that the antimycobacterial activity of these compounds is strongly dependent on hydrogen-bonding donors, molecular refraction and also molecular connectivity indices for 2nd order.
QSAR for Antimycobacterial Activity of β-Thia Adduct of Chalcone and Diazachalcone Derivatives
doi:10.11648/j.ijctc.20140203.11
International Journal of Computational and Theoretical Chemistry
2014-07-26
© Science Publishing Group
Younes Abrouki
Abdelkader Anouzla
Hayat Loukili
Ahmed Rayadh
Driss Zakarya
Mohamed Zahouily
QSAR for Antimycobacterial Activity of β-Thia Adduct of Chalcone and Diazachalcone Derivatives
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3
25
25
2014-07-26
2014-07-26
10.11648/j.ijctc.20140203.11
http://www.sciencepublishinggroup.com/journal/paperinfo.aspx?journalid=228&doi=10.11648/j.ijctc.20140203.11
© Science Publishing Group
Computation of Electronic Proprieties of the DNA and RNA Bases
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In this paper the authors report the optimizations of the DNA and RNA bases (adenine, cytosine, thymine, guanine and uracil) for to determine the electronic proprieties and are employed the LSDA/6-31++G, PBE/6-31++G, PBE/LANL2DZ and PBE/SDD levels of theory both in gas phase and in the presence of the solvent water with the actual implementation of the polarized continuum model of Tomasi (PCM). And to provide the IPV, EAV, hardness, dipole moment and electronegativity (χ). The vibrational frequencies are description to purine and pyrimidine bases.
In this paper the authors report the optimizations of the DNA and RNA bases (adenine, cytosine, thymine, guanine and uracil) for to determine the electronic proprieties and are employed the LSDA/6-31++G, PBE/6-31++G, PBE/LANL2DZ and PBE/SDD levels of theory both in gas phase and in the presence of the solvent water with the actual implementation of the polarized continuum model of Tomasi (PCM). And to provide the IPV, EAV, hardness, dipole moment and electronegativity (χ). The vibrational frequencies are description to purine and pyrimidine bases.
Computation of Electronic Proprieties of the DNA and RNA Bases
doi:10.11648/j.ijctc.20140204.11
International Journal of Computational and Theoretical Chemistry
2014-10-17
© Science Publishing Group
Mariana Virginia Popa
Computation of Electronic Proprieties of the DNA and RNA Bases
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2014-10-17
2014-10-17
10.11648/j.ijctc.20140204.11
http://www.sciencepublishinggroup.com/journal/paperinfo.aspx?journalid=228&doi=10.11648/j.ijctc.20140204.11
© Science Publishing Group
Theoretical Study of the Reaction Mechanism Ba, Ti, O in the Early Growth of BTO Thin Films
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We use the DMol3 program based on density functional theory(DFT) to clarify the processes of microcosmic reactions and the particle states in the early growth of BaTiO3 (BTO) thin films. This research is important for optimal preparation and structure control of BTO thin films. After designing and optimizing some possible intermediate states, we find that the molecules may serve as nucleation sites for BTO growth. This occurs by combining TiO2 with BaO molecules to form BaTiO3 with the G conformation, which is similar to a quarter of a BTO unit cell. By virtue of understanding these mechanisms, perovskite-structured BTO thin films are formed.
We use the DMol3 program based on density functional theory(DFT) to clarify the processes of microcosmic reactions and the particle states in the early growth of BaTiO3 (BTO) thin films. This research is important for optimal preparation and structure control of BTO thin films. After designing and optimizing some possible intermediate states, we find that the molecules may serve as nucleation sites for BTO growth. This occurs by combining TiO2 with BaO molecules to form BaTiO3 with the G conformation, which is similar to a quarter of a BTO unit cell. By virtue of understanding these mechanisms, perovskite-structured BTO thin films are formed.
Theoretical Study of the Reaction Mechanism Ba, Ti, O in the Early Growth of BTO Thin Films
doi:10.11648/j.ijctc.20140205.11
International Journal of Computational and Theoretical Chemistry
2014-11-04
© Science Publishing Group
Chun Yang
XiaoQin Liang
Ping Huang
Theoretical Study of the Reaction Mechanism Ba, Ti, O in the Early Growth of BTO Thin Films
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5
45
45
2014-11-04
2014-11-04
10.11648/j.ijctc.20140205.11
http://www.sciencepublishinggroup.com/journal/paperinfo.aspx?journalid=228&doi=10.11648/j.ijctc.20140205.11
© Science Publishing Group
The Electronic Proprieties of the Silver Clusters
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En this article are presented the theorics work for clarify the structure of all silver cluster and are compareted the results with experimental data for see which levels of theory describe better the propriety of the silver cluster. For Ag2-A5 are reach different value of the bond, ionization potentials and frequencies, electron affinities and biding energy method employed ab initio and relativystic bases. Are optimization with the following levels of theorie: HF/LANL1MB, HF/LANL2MB, HF/LANL2DZ, B3LYP/LANL1MB, B3LYP/LANL2MB, B3LYP/LANL2DZ, MP2/LANL2DZ, DFT/PBE/SDD and DFT/PBE/3-21G**.
En this article are presented the theorics work for clarify the structure of all silver cluster and are compareted the results with experimental data for see which levels of theory describe better the propriety of the silver cluster. For Ag2-A5 are reach different value of the bond, ionization potentials and frequencies, electron affinities and biding energy method employed ab initio and relativystic bases. Are optimization with the following levels of theorie: HF/LANL1MB, HF/LANL2MB, HF/LANL2DZ, B3LYP/LANL1MB, B3LYP/LANL2MB, B3LYP/LANL2DZ, MP2/LANL2DZ, DFT/PBE/SDD and DFT/PBE/3-21G**.
The Electronic Proprieties of the Silver Clusters
doi:10.11648/j.ijctc.20140206.11
International Journal of Computational and Theoretical Chemistry
2014-12-22
© Science Publishing Group
Mariana Virginia Popa
The Electronic Proprieties of the Silver Clusters
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6
68
68
2014-12-22
2014-12-22
10.11648/j.ijctc.20140206.11
http://www.sciencepublishinggroup.com/journal/paperinfo.aspx?journalid=228&doi=10.11648/j.ijctc.20140206.11
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A Theoretical Method for Calculating the Bond Integral Parameter for Atomic Orbitals
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In molecular orbital theory, the bond integral parameter k is used to calculate the bond integral β for different molecular structures. The bond integral parameter k, which represents the ratio of bond integrals between two atoms of a diatomic molecule, is a function of the bond length. This parameter is usually obtained empirically; however, it will be shown that k can be determined analytically by utilizing the overlap integral S. k will be calculated for different atomic orbital combinations (ss,pp) of σ and π interactions as a function of bond length for a carbon-carbon diatomic molecule. The results, which are represented graphically, indicate that different atomic orbitals in different interactions can have the same, or very close to the same, k values. The graphs reveal some significant features for the different atomic orbital combinations with respect to magnitude and profile, as well as illustrate good agreement with experimental results, which validates the utilization of the overlap integral calculation method for the determination of the bond integral parameter k.
In molecular orbital theory, the bond integral parameter k is used to calculate the bond integral β for different molecular structures. The bond integral parameter k, which represents the ratio of bond integrals between two atoms of a diatomic molecule, is a function of the bond length. This parameter is usually obtained empirically; however, it will be shown that k can be determined analytically by utilizing the overlap integral S. k will be calculated for different atomic orbital combinations (ss,pp) of σ and π interactions as a function of bond length for a carbon-carbon diatomic molecule. The results, which are represented graphically, indicate that different atomic orbitals in different interactions can have the same, or very close to the same, k values. The graphs reveal some significant features for the different atomic orbital combinations with respect to magnitude and profile, as well as illustrate good agreement with experimental results, which validates the utilization of the overlap integral calculation method for the determination of the bond integral parameter k.
A Theoretical Method for Calculating the Bond Integral Parameter for Atomic Orbitals
doi:10.11648/j.ijctc.20150301.11
International Journal of Computational and Theoretical Chemistry
2015-04-15
© Science Publishing Group
Dale J. Igram
Jason W. Ribblett
Eric R. Hedin
Yong S. Joe
A Theoretical Method for Calculating the Bond Integral Parameter for Atomic Orbitals
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1
5
5
2015-04-15
2015-04-15
10.11648/j.ijctc.20150301.11
http://www.sciencepublishinggroup.com/journal/paperinfo.aspx?journalid=228&doi=10.11648/j.ijctc.20150301.11
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Computational Study of the Mechanism of the Oxidation of Hydrazine / Hydrazinium Ion by Iodine in the Gas Phase
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The reaction mechanisms of the oxidation of hydrazine / hydrazinium ion by iodine have been studied using 6311+G** basis set of the density functional theory (DFT) method at the B3LYP level of computation. The study shows that the oxidation reactions can proceed via four independent routes or pathways that can be separately monitored. Two of the proposed pathways involved a two-step reaction mechanism each, in which two transition states were produced while each of the other two routes involved three-step reaction mechanism in which three activated complexes were produced. The results obtained were based on the analyses of the computational energetics of the optimized reactants, intermediates, transition states and products of the reaction of iodine with hydrazine / hydrazinium ion. The study showed that all the four proposed routes were possible by comparing the enthalpies of reactions of the four proposed pathways as well as the activation barriers of the respective rate determining steps which were found to be reasonably acceptable. Rate laws, which were consistent with the written mechanisms, were also derived for each of the proposed mechanisms.
The reaction mechanisms of the oxidation of hydrazine / hydrazinium ion by iodine have been studied using 6311+G** basis set of the density functional theory (DFT) method at the B3LYP level of computation. The study shows that the oxidation reactions can proceed via four independent routes or pathways that can be separately monitored. Two of the proposed pathways involved a two-step reaction mechanism each, in which two transition states were produced while each of the other two routes involved three-step reaction mechanism in which three activated complexes were produced. The results obtained were based on the analyses of the computational energetics of the optimized reactants, intermediates, transition states and products of the reaction of iodine with hydrazine / hydrazinium ion. The study showed that all the four proposed routes were possible by comparing the enthalpies of reactions of the four proposed pathways as well as the activation barriers of the respective rate determining steps which were found to be reasonably acceptable. Rate laws, which were consistent with the written mechanisms, were also derived for each of the proposed mechanisms.
Computational Study of the Mechanism of the Oxidation of Hydrazine / Hydrazinium Ion by Iodine in the Gas Phase
doi:10.11648/j.ijctc.20150302.11
International Journal of Computational and Theoretical Chemistry
2015-05-08
© Science Publishing Group
Gideon Adamu Shallangwa
Adamu Uzairu
Victor Olatunji Ajibola
Hamza Abba
Computational Study of the Mechanism of the Oxidation of Hydrazine / Hydrazinium Ion by Iodine in the Gas Phase
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18
18
2015-05-08
2015-05-08
10.11648/j.ijctc.20150302.11
http://www.sciencepublishinggroup.com/journal/paperinfo.aspx?journalid=228&doi=10.11648/j.ijctc.20150302.11
© Science Publishing Group
Effect of Different Shape of Periodic Forces on Chaotic Oscillation in Brusselator Chemical System
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Bifurcations of periodic orbits and chaos in the Brusselator chemical reaction with different shape of external periodic forces are studied numerically. The external periodic forces considered are sine wave, square-wave, rectified sine wave, symmetric saw-tooth wave, asymmetric saw-tooth wave and modulus of sine wave. Period doubling bifurcations, chaos, reverse period doubling bifurcations, quasiperiodic bifurcations are found to occur due to the applied forces. Parametric regimes where suppression of chaos occurs are predicted. Numerical investigations including bifurcation diagram, maximal Lyapunov exponent, Poincare map, Phase portrait and time series plot are used to detect chaos, quasiperiodic and periodic orbits.
Bifurcations of periodic orbits and chaos in the Brusselator chemical reaction with different shape of external periodic forces are studied numerically. The external periodic forces considered are sine wave, square-wave, rectified sine wave, symmetric saw-tooth wave, asymmetric saw-tooth wave and modulus of sine wave. Period doubling bifurcations, chaos, reverse period doubling bifurcations, quasiperiodic bifurcations are found to occur due to the applied forces. Parametric regimes where suppression of chaos occurs are predicted. Numerical investigations including bifurcation diagram, maximal Lyapunov exponent, Poincare map, Phase portrait and time series plot are used to detect chaos, quasiperiodic and periodic orbits.
Effect of Different Shape of Periodic Forces on Chaotic Oscillation in Brusselator Chemical System
doi:10.11648/j.ijctc.20150303.11
International Journal of Computational and Theoretical Chemistry
2015-06-23
© Science Publishing Group
Guruparan S.
Ravindran Durai Nayagam B.
Jeyakumari S.
Chinnathambi V.
Effect of Different Shape of Periodic Forces on Chaotic Oscillation in Brusselator Chemical System
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27
27
2015-06-23
2015-06-23
10.11648/j.ijctc.20150303.11
http://www.sciencepublishinggroup.com/journal/paperinfo.aspx?journalid=228&doi=10.11648/j.ijctc.20150303.11
© Science Publishing Group
The Electronic Properties of the Silver Clusters in Gas Phase and Water
http://www.sciencepublishinggroup.com/journal/paperinfo.aspx?journalid=228&doi=10.11648/j.ijctc.s.2015030301.13
En this article are presented the theorics work for clarify the structure of all silver cluster in gas phase and water and are compareted the results with experimental data for see which levels of theory describe better the propriety of the silver cluster. Are calculated different value of the bond, ionization potentials and frequencies, electron affinities and binding energy method employed ab initio and relativystic bases. Are optimization with the following levels of theorie: HF/LANL1MB, HF/LANL2MB, HF/LANL2DZ, B3LYP/LANL1MB, B3LYP/LANL2MB, B3LYP/LANL2DZ, MP2/LANL2DZ, DFT/PBE/SDD and DFT/PBE/3-21G**.
En this article are presented the theorics work for clarify the structure of all silver cluster in gas phase and water and are compareted the results with experimental data for see which levels of theory describe better the propriety of the silver cluster. Are calculated different value of the bond, ionization potentials and frequencies, electron affinities and binding energy method employed ab initio and relativystic bases. Are optimization with the following levels of theorie: HF/LANL1MB, HF/LANL2MB, HF/LANL2DZ, B3LYP/LANL1MB, B3LYP/LANL2MB, B3LYP/LANL2DZ, MP2/LANL2DZ, DFT/PBE/SDD and DFT/PBE/3-21G**.
The Electronic Properties of the Silver Clusters in Gas Phase and Water
doi:10.11648/j.ijctc.s.2015030301.13
International Journal of Computational and Theoretical Chemistry
2015-03-10
© Science Publishing Group
Mariana Virginia Popa
The Electronic Properties of the Silver Clusters in Gas Phase and Water
3
3
57
57
2015-03-10
2015-03-10
10.11648/j.ijctc.s.2015030301.13
http://www.sciencepublishinggroup.com/journal/paperinfo.aspx?journalid=228&doi=10.11648/j.ijctc.s.2015030301.13
© Science Publishing Group
The AgxSiy (x=1-5, y=1-5, x+y=5) Clusters
http://www.sciencepublishinggroup.com/journal/paperinfo.aspx?journalid=228&doi=10.11648/j.ijctc.s.2015030301.12
En this paper are presented the theorics work for clarify the structure of all cluster which levels of theory describe better the propriety of the AgxSiy cluster. For AgxSiy are reach different value of the bond, ionization potentials and frequencies, electron affinities and biding energy method employed ab initio and relativystic bases. Are optimization with PBE/LANL2DZ level of theorie. I employed relativistic LANL2DZ bases in this work and PBE functional of exchenge and coreletion Perdew-Burke-Ernzerhof who employed the GCA(Genaralizad Gradient Approximation), this are better for the energy, and different energy structurale.
En this paper are presented the theorics work for clarify the structure of all cluster which levels of theory describe better the propriety of the AgxSiy cluster. For AgxSiy are reach different value of the bond, ionization potentials and frequencies, electron affinities and biding energy method employed ab initio and relativystic bases. Are optimization with PBE/LANL2DZ level of theorie. I employed relativistic LANL2DZ bases in this work and PBE functional of exchenge and coreletion Perdew-Burke-Ernzerhof who employed the GCA(Genaralizad Gradient Approximation), this are better for the energy, and different energy structurale.
The AgxSiy (x=1-5, y=1-5, x+y=5) Clusters
doi:10.11648/j.ijctc.s.2015030301.12
International Journal of Computational and Theoretical Chemistry
2015-03-10
© Science Publishing Group
Mariana Virginia Popa
The AgxSiy (x=1-5, y=1-5, x+y=5) Clusters
3
3
35
35
2015-03-10
2015-03-10
10.11648/j.ijctc.s.2015030301.12
http://www.sciencepublishinggroup.com/journal/paperinfo.aspx?journalid=228&doi=10.11648/j.ijctc.s.2015030301.12
© Science Publishing Group
The AgxSiy(x=1-5, y=1-5) Clusters with Electronegativity, Molecular Orbitals and SCF Density
http://www.sciencepublishinggroup.com/journal/paperinfo.aspx?journalid=228&doi=10.11648/j.ijctc.s.2015030301.11
In this work I calculated the optimization geometry of AgxSiy clusters with PBE/LANL2DZ level of theorie and I plot the molecular orbitals and SCF density. For the proprieties of clusters I claculated the electronegativity for employed the results in the chemical reaction. The HOMO and LUMO for neutral clusters are very different that anion and cation and not all atoms are greater density of electron. The SCF density in the structure of cluster are sferical density. The 8.36 and 7.26 eV are the mayor values obtained for the electronegativity.
In this work I calculated the optimization geometry of AgxSiy clusters with PBE/LANL2DZ level of theorie and I plot the molecular orbitals and SCF density. For the proprieties of clusters I claculated the electronegativity for employed the results in the chemical reaction. The HOMO and LUMO for neutral clusters are very different that anion and cation and not all atoms are greater density of electron. The SCF density in the structure of cluster are sferical density. The 8.36 and 7.26 eV are the mayor values obtained for the electronegativity.
The AgxSiy(x=1-5, y=1-5) Clusters with Electronegativity, Molecular Orbitals and SCF Density
doi:10.11648/j.ijctc.s.2015030301.11
International Journal of Computational and Theoretical Chemistry
2015-03-10
© Science Publishing Group
Mariana Virginia Popa
The AgxSiy(x=1-5, y=1-5) Clusters with Electronegativity, Molecular Orbitals and SCF Density
3
3
18
18
2015-03-10
2015-03-10
10.11648/j.ijctc.s.2015030301.11
http://www.sciencepublishinggroup.com/journal/paperinfo.aspx?journalid=228&doi=10.11648/j.ijctc.s.2015030301.11
© Science Publishing Group