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  • About
  • The Global ETD Search service is a free service for researchers to find electronic theses and dissertations. This service is provided by the Networked Digital Library of Theses and Dissertations.
    Our metadata is collected from universities around the world. If you manage a university/consortium/country archive and want to be added, details can be found on the NDLTD website.
1

Explorando aspectos energéticos, estruturais e cinéticos de espécies químicas utilizando abordagens altamente correlacionadas / Exploring energetic, structural and kinetic aspects of chemical species using highly correlated approaches

Alves, Tiago Vinicius 19 April 2013 (has links)
Neste estudo, parâmetros estruturais, energéticos e da frequências vibracionais para os estados X 3Σ- e A 3II do radical CNN e X 2II das espécies iônicas CNN+ e CNN- foram obtidos no nível de teoria CCSD(T)/CBST-5. No estudo termoquímico, os valores para o calor de formação da espécie neutra foram, ΔHf (O K) = 138,89 kcal/mol e ΔHf (298,15 K) = 139,65 kcal/mol. Para o potencial de ionização e a afinidade eletrônica, os resultados deste trabalho são 10,969 e 1,743 eV, respectivamente. Otimizações de geometria para os estados eletrônicos X 3Σ-, A 3II, a 1Δ, b 1Σ+, c 1II, d X 1Σ- e B 3Σ- realizadas com a metodologia MRCI nos permitiram obter valores para Te. Além disso, as energias de transição vertical para 15 estados eletrônicos também foram determinadas. Utilizando o nível de teoria CCSD(T)-F12b/CBSD-Q, geometrias de equilíbrio e frequências vibracionais harmônicas e anarmônicas foram estimadas para a molécula C30 e seu ânion C30-. Uma avaliação dos efeitos que inclusão dos elétrons do caroço no cálculo de diferentes propriedades foi realizada. Descrevemos a primeira determinação do calor de formação para a molécula C3O, ΔHf (0 K) = 79,41 kcal/mol e ΔHf( (298,15 K) = 83,39 kcal/mol, além do cálculo da afinidade eletrônica (1,114 eV). No que se refere à cinética e à dinâmica química, a determinação das constantes de velocidade foi realizada para duas reações de abstração de hidrogênio. Na primeira, as constantes de velocidade para a reação S (3P) + CH4 → SH + CH3, numa ampla faixa de temperaturas (T = 200 - 3000 K), foram determinadas utilizando SS-VTST/MT combinada com cálculos DFT/M05-2X/MG3S. A 1200 K, a constante de velocidade CVT/SCT para este processo (2,85 x 10-14 cm3 molécula-1 s-1) está em excelente concordância com o resultado experimental (8,14 x 10-14 cm3 molécula-1 s-1). Na segunda, o estudo a reação de abstração de hidrogênio do butanoato de metila por hidrogênio atômico foi realizada utilizando a abordagem cinética MS-VTST/MT combidada com cálculos MPWB1K/G- 31+G(d,p). Nesta aproximação cinética, a anarmonicidade associada às torções angulares amortecidas, bem como o acoplamento entre elas foram consideradas no cálculo das constante de velocidade. Neste processo, verificamos que a inclusão da anarmonicidade torcional nas constantes de velocidade aumenta a constante de velocidade em aproximadamente 8-10% a altas temperaturas (T = 1000 -2000 K). A temperaturas mais baixas, os efeitos de tunelamento são predominantes e a constante de velocidade CVT/SCT para a reação CH3CH2CH2COOCH3 + H (2S) → CH2CH2CH2COOCH3 + H (2S) a 300 K (6,17 x 10-18 cm3 molécula-1 s-1) é 8,2 vezes maior que a obtida com CVT (5,07 x 10-17 cm3 molécula-1 s-1). / In this study, the structures, energies and vibrational frequencies for the X 3Σ- e A3II electronic states of CNN, and X 2II of the ions CNN+ and CNN- were obtained at the CCSD(T)/CBST-5 level of theory. Additionally, we also estimated the heats of formation for the neutral species ΔHf (0 K) = 138.89 kcal/mol and ΔHf(298.15 K) = 139.65 kcal/mol. For the ionization potential and electron affinities, this work predicted the values of 10.969 e 1.743 eV, respectively. Geometry optimizations for the electronic states 3Σ-, A 3II, a 1Δ, b 1Σ+, c 1II, d X 1Σ- e B 3Σ- performed with the MRCI approach allowed us to compute the excitation energies (Te). Furthermore, vertical transition energies were also calculated for 15 electronic states. Using the CCSD(T)-F12b/CBSD-Q level of theory, equilibrium geometries, and harmonic and anharmonic vibrational frequencies were estimated for the C3O molecule and the anion C3O-. An assessment of the effects of inclusion of core electrons in the calculation of some properties was also carried out. The determination of the heat of formation of the molecule C3O (ΔHf (0 K) = 79.41 kcal/mol and ΔHf (298.15 K) = 83.39 kcal/mol), and its electron affinity (1,114 eV) were the first ones reported in the literature. In the kinetics investigation, we estimated the rate constants for two hydrogen abstraction reactions. Rate constants for the reaction S(3P) + CH4 → SH + CH3 were predicted for a wide range of temperatures (T = 200 - 3000 K) using VTST/MT combined with DFT/M05-2X/MG3S calculations. At 1200 K, the calculated rate constant CVT/SCT for this process is 2.85 x 10-14 cm3 molecule-1 s-1. For the reaction of hydrogen abstraction from methyl butanoate by a hydrogen atom, the MS-VTST/MT method combined with the density functional MPWB1K/G-31+G(d,p) was employed. In this study, anharmonic torsional hindered rotations were considered in calculations of the rate constants. At high temperatures, the inclusion of torsional anharmonicity increases the rate constants by approximately 8-10%. At low temperatures, tunneling effects are predominant and the rate constant CVT/SCT (6.17 x 10-18 cm3 molécula-1 s-1) is 8.2 times higher than the CVT one (5.07 x 10-17 cm3 molécula-1 s-1 ).
2

Explorando aspectos energéticos, estruturais e cinéticos de espécies químicas utilizando abordagens altamente correlacionadas / Exploring energetic, structural and kinetic aspects of chemical species using highly correlated approaches

Tiago Vinicius Alves 19 April 2013 (has links)
Neste estudo, parâmetros estruturais, energéticos e da frequências vibracionais para os estados X 3Σ- e A 3II do radical CNN e X 2II das espécies iônicas CNN+ e CNN- foram obtidos no nível de teoria CCSD(T)/CBST-5. No estudo termoquímico, os valores para o calor de formação da espécie neutra foram, ΔHf (O K) = 138,89 kcal/mol e ΔHf (298,15 K) = 139,65 kcal/mol. Para o potencial de ionização e a afinidade eletrônica, os resultados deste trabalho são 10,969 e 1,743 eV, respectivamente. Otimizações de geometria para os estados eletrônicos X 3Σ-, A 3II, a 1Δ, b 1Σ+, c 1II, d X 1Σ- e B 3Σ- realizadas com a metodologia MRCI nos permitiram obter valores para Te. Além disso, as energias de transição vertical para 15 estados eletrônicos também foram determinadas. Utilizando o nível de teoria CCSD(T)-F12b/CBSD-Q, geometrias de equilíbrio e frequências vibracionais harmônicas e anarmônicas foram estimadas para a molécula C30 e seu ânion C30-. Uma avaliação dos efeitos que inclusão dos elétrons do caroço no cálculo de diferentes propriedades foi realizada. Descrevemos a primeira determinação do calor de formação para a molécula C3O, ΔHf (0 K) = 79,41 kcal/mol e ΔHf( (298,15 K) = 83,39 kcal/mol, além do cálculo da afinidade eletrônica (1,114 eV). No que se refere à cinética e à dinâmica química, a determinação das constantes de velocidade foi realizada para duas reações de abstração de hidrogênio. Na primeira, as constantes de velocidade para a reação S (3P) + CH4 → SH + CH3, numa ampla faixa de temperaturas (T = 200 - 3000 K), foram determinadas utilizando SS-VTST/MT combinada com cálculos DFT/M05-2X/MG3S. A 1200 K, a constante de velocidade CVT/SCT para este processo (2,85 x 10-14 cm3 molécula-1 s-1) está em excelente concordância com o resultado experimental (8,14 x 10-14 cm3 molécula-1 s-1). Na segunda, o estudo a reação de abstração de hidrogênio do butanoato de metila por hidrogênio atômico foi realizada utilizando a abordagem cinética MS-VTST/MT combidada com cálculos MPWB1K/G- 31+G(d,p). Nesta aproximação cinética, a anarmonicidade associada às torções angulares amortecidas, bem como o acoplamento entre elas foram consideradas no cálculo das constante de velocidade. Neste processo, verificamos que a inclusão da anarmonicidade torcional nas constantes de velocidade aumenta a constante de velocidade em aproximadamente 8-10% a altas temperaturas (T = 1000 -2000 K). A temperaturas mais baixas, os efeitos de tunelamento são predominantes e a constante de velocidade CVT/SCT para a reação CH3CH2CH2COOCH3 + H (2S) → CH2CH2CH2COOCH3 + H (2S) a 300 K (6,17 x 10-18 cm3 molécula-1 s-1) é 8,2 vezes maior que a obtida com CVT (5,07 x 10-17 cm3 molécula-1 s-1). / In this study, the structures, energies and vibrational frequencies for the X 3Σ- e A3II electronic states of CNN, and X 2II of the ions CNN+ and CNN- were obtained at the CCSD(T)/CBST-5 level of theory. Additionally, we also estimated the heats of formation for the neutral species ΔHf (0 K) = 138.89 kcal/mol and ΔHf(298.15 K) = 139.65 kcal/mol. For the ionization potential and electron affinities, this work predicted the values of 10.969 e 1.743 eV, respectively. Geometry optimizations for the electronic states 3Σ-, A 3II, a 1Δ, b 1Σ+, c 1II, d X 1Σ- e B 3Σ- performed with the MRCI approach allowed us to compute the excitation energies (Te). Furthermore, vertical transition energies were also calculated for 15 electronic states. Using the CCSD(T)-F12b/CBSD-Q level of theory, equilibrium geometries, and harmonic and anharmonic vibrational frequencies were estimated for the C3O molecule and the anion C3O-. An assessment of the effects of inclusion of core electrons in the calculation of some properties was also carried out. The determination of the heat of formation of the molecule C3O (ΔHf (0 K) = 79.41 kcal/mol and ΔHf (298.15 K) = 83.39 kcal/mol), and its electron affinity (1,114 eV) were the first ones reported in the literature. In the kinetics investigation, we estimated the rate constants for two hydrogen abstraction reactions. Rate constants for the reaction S(3P) + CH4 → SH + CH3 were predicted for a wide range of temperatures (T = 200 - 3000 K) using VTST/MT combined with DFT/M05-2X/MG3S calculations. At 1200 K, the calculated rate constant CVT/SCT for this process is 2.85 x 10-14 cm3 molecule-1 s-1. For the reaction of hydrogen abstraction from methyl butanoate by a hydrogen atom, the MS-VTST/MT method combined with the density functional MPWB1K/G-31+G(d,p) was employed. In this study, anharmonic torsional hindered rotations were considered in calculations of the rate constants. At high temperatures, the inclusion of torsional anharmonicity increases the rate constants by approximately 8-10%. At low temperatures, tunneling effects are predominant and the rate constant CVT/SCT (6.17 x 10-18 cm3 molécula-1 s-1) is 8.2 times higher than the CVT one (5.07 x 10-17 cm3 molécula-1 s-1 ).
3

Contribution à l'étude quantique du carbure de tungstène neutre (WC) et ionisé (WCq+, q=1, 2) / Contribution to the quantum study of the tungsten carbide neutral (WC) and ionized (WCq+, q = 1, 2)

Sabor, Said 18 April 2015 (has links)
Les carbures et oxydes des métaux de transition sont d'une importance capitale dans le domaine industriel voir catalytique. Le carbure de tungstène WC a été identifié comme un bon substituant des métaux nobles tel que le platine dans le domaine catalytique. Le but de ce travail de thèse est d'appliquer des méthodes de chimie quantique les plus poussées pour déterminer la structure électronique, la stabilité et la nature de liaison chimique des diatomiques WC et WC2+. Notre recherche préliminaire est motivée par les données spectroscopiques disponibles sur W, W+, W2+, WC et WC2+. La méthodologie adoptée, CASSCF/MRCI/MRCI+Q/aug-cc-pV5Z(-PP) implémentée dans le code MOLPRO, consiste à réaliser des calculs quantique tenant en compte des effets de corrélation et relativistes avec un traitement spécifique du couplage spin−orbite pour la recherche des courbes d'énergie potentielle de l'état fondamental et des états excités de plus basses énergies de WCn+ (n=0-2) tout en utilisant une base suffisamment étendue. Les résultats de ce travail sont en bon accord avec ceux disponibles dans la littérature. En outre, dans ce travail nous avons confirmé pour la première fois que le carbure diatomique dicationique WC2+ est thermodynamiquement stable / Metal carbides and oxides are more interesting in catalytic and industrial domains. Tungsten carbide WC has been detected as serious substituent of platinum Pt catalytic. The ultimate goal of this thesis is theoretical studies of electronic structure, stability and the bound nature on WC, WO and its cations. Our preliminary research were motiving by the available spectroscopic data on W, W+, W2+, WC et WC2+. We used the methodology (CASSCF/MRCI/MRCI+Q/aug-cc-pV5Z(-PP)) implemented on MOLPRO package to perform quantum calculations with high accuracy taking into account the correlation and relativistic effects with a specific treatment of spin orbit coupling for some low lying excited electronic states of WCn+, (n=0, 1 et 2). Our results are shown in good agreement with those available in the literature. Furthermore, in this work for the first time we demonstrated that a carbide dication (WC2+) is thermodynamically stable
4

Estudo de energias de dupla ionização e de ligação de elétron por Monte Carlo Quântico e métodos pós-hartree-fock / Double ionization energies and electron binding energies : a study by Quantum Monte Carlo and post-hartree-fock methods

Streit, Livia, 1986- 21 August 2018 (has links)
Orientador: Rogério Custodio / Tese (doutorado) - Universidade Estadual de Campinas, Instituto de Química / Made available in DSpace on 2018-08-21T05:01:18Z (GMT). No. of bitstreams: 1 Streit_Livia_D.pdf: 1852639 bytes, checksum: 1d6bd6190d21b329d992dfe5f74f8993 (MD5) Previous issue date: 2012 / Resumo: O estudo de processos fotoeletrônicos, como energias de dupla ionização é de grante interesse teórico e experimental na área da física molecular. Cálculos e medidas experimentais de energias de dupla ionização e de energias de ligação de elétron envolvem o entendimento de correlação e relaxação eletrônica. A consideração de tais efeitos é indispensável para a obtenção de resultados precisos. No presente trabalho, tais processos fotoeletrônicos são estudados com métodos Pós-Hartree-Fock e Monte Carlo Quântico (MCQ). No último caso, o método foi adaptado de maneira a utilizar um tipo diferente de função de onda. A primeira parte desta tese envolve o estudo de energias de dupla ionização. O objetivo prinicipal é a análise do tipo de função de onda tentativa no método MCQ. Três diferentes formas foram estudadas: Uma função Hartree-Fock monodeterminante com uma função de correlação eletrônica explícita de Boys-Handy otimizada para a molécula; uma função CI multideterminante; e ainda, uma função de onda multideterminante construída a partir de orbitais de Dyson. Para obter a função de onda de Dyson, um extenso trabalho envolvendo estudo e programação do programa de cálculo de estrutura eletrônica Gaussian 09 foi necessário. A primeira parte da tese ainda envolve o estudo de energias de dupla ionização por métodos Interação de Configurações Multireferência MRCI e Gaussian-3 G3. Os resultados obtidos são comparados aos resultados obtidos por MCQ. A segunda parte da tese compreende o estudo de energias de ligação de elétron de complexos de gases nobres com o ânion Uracila. A coexistência de ânions em que o orbital singularmente ocupado apresenta características de um orbital de valência e de um orbital muito difuso é investigada através de análise de geometria e do cálculo de energias de afinidade eletrônica e de ligação de elétron dos complexos neutros e aniônicos / Abstract: The study of photoelectron processes such as double ionization energies has become a very interesting field in experimental and theoretical molecular physics. Calculation and experimental measure of double ionization energies and electron binding energies involve understanding of electron correlation and relaxation energies. Consideration of those effects are a requisite in order to predict precise values. In this work, those photoelectron processes are studied with post-Hartree-Fock and Quantum Monte Carlo (QMC) methods. In the latter case, the method was also modified to take in account a different type of wavefunction. The first part of this thesis is concerned with the study of double ionization energies. The main objective of this work is the analysis of the type of trial wavefunction in QMC method. Three different forms were studied: A single determinant Hartree-Fock function, with the Boys-Handy explicit electron correlation function optimized for the molecule; a multi-determinant CI wavefunction; and finally, a multi-determinant wavefunction built from Dyson orbitals. In order to obtain the Dyson wavefunction, an extensive work on studying and programming the electron structure package Gaussian 09 was necessary. The first part still comprises the study of double ionization energies with MRCI and G3 methods. The results thus obtained were compared to the QMC results. The second part of this thesis embraces the study of electron binding energies of uracil¿noble-gas complexes. The coexistence of valence and diffuse¿bound anions of U(Xe), suggested by experimental studies is investigated with geometry analysis and calculation of adiabatic electron affinities and vertical electron detachment energies of the neutral an anionic complexes / Doutorado / Físico-Química / Doutor em Ciências
5

Contribution à l'étude quantique du carbure de tungstène neutre (WC) et ionisé (WCq+, q=1, 2) / Contribution to the quantum study of the tungsten carbide neutral (WC) and ionized (WCq+, q = 1, 2)

Sabor, Said 18 April 2015 (has links)
Les carbures et oxydes des métaux de transition sont d'une importance capitale dans le domaine industriel voir catalytique. Le carbure de tungstène WC a été identifié comme un bon substituant des métaux nobles tel que le platine dans le domaine catalytique. Le but de ce travail de thèse est d'appliquer des méthodes de chimie quantique les plus poussées pour déterminer la structure électronique, la stabilité et la nature de liaison chimique des diatomiques WC et WC2+. Notre recherche préliminaire est motivée par les données spectroscopiques disponibles sur W, W+, W2+, WC et WC2+. La méthodologie adoptée, CASSCF/MRCI/MRCI+Q/aug-cc-pV5Z(-PP) implémentée dans le code MOLPRO, consiste à réaliser des calculs quantique tenant en compte des effets de corrélation et relativistes avec un traitement spécifique du couplage spin−orbite pour la recherche des courbes d'énergie potentielle de l'état fondamental et des états excités de plus basses énergies de WCn+ (n=0-2) tout en utilisant une base suffisamment étendue. Les résultats de ce travail sont en bon accord avec ceux disponibles dans la littérature. En outre, dans ce travail nous avons confirmé pour la première fois que le carbure diatomique dicationique WC2+ est thermodynamiquement stable / Metal carbides and oxides are more interesting in catalytic and industrial domains. Tungsten carbide WC has been detected as serious substituent of platinum Pt catalytic. The ultimate goal of this thesis is theoretical studies of electronic structure, stability and the bound nature on WC, WO and its cations. Our preliminary research were motiving by the available spectroscopic data on W, W+, W2+, WC et WC2+. We used the methodology (CASSCF/MRCI/MRCI+Q/aug-cc-pV5Z(-PP)) implemented on MOLPRO package to perform quantum calculations with high accuracy taking into account the correlation and relativistic effects with a specific treatment of spin orbit coupling for some low lying excited electronic states of WCn+, (n=0, 1 et 2). Our results are shown in good agreement with those available in the literature. Furthermore, in this work for the first time we demonstrated that a carbide dication (WC2+) is thermodynamically stable
6

Ab Initio investigation of the electronic structure and rovibrational spectroscopy of group-I and II metal hydrides and helides

Page, Alister J. January 2008 (has links)
Research Doctorate - Doctor of Philosophy (PhD) / (**Note: this abstract is a plain text version of the author's abstract, the original of which contains characters and symbols which cannot be accurately represented in this format. The properly formatted abstract can be viewed in the Abstract and Thesis files above.**) The electronic structure and rovibrational spectroscopy of MH2, MHn+2, HMHen+ and MHen+2 (M = Li, Be, Na, Mg, K, Ca; n = 1, 2) have been investigated using correlated ab initio ansatz. In order to determine the efficacy of various electronic structure methods with respect to Group-I and II hydrides and helides, atomic properties of Li, Be,Na, Mg, K and Ca were calculated. Relativistically-corrected UCCSD(T) and ICMRCI(+Q) were deemed to be the most suitable ansatz with respect to both efficiency and accuracy. The lowest 2A1 and 2Σ- states of MH2 were found to be purely repulsive, in agreement with previous predictions. The main factor determining the structure and stability of the excited states of MH2 was the relative orientations and occupations of the valence p atomic orbital of M and the H2 1Ou orbital. The ground states of MHn+2 were found to be the result of the charge-quadrupole interaction between Mn+ and the H2 molecular subunit. The structures of the ground states of HMHe+ were extremely uxional with respect to the central bond angle co-ordinate. The ground state PESs of MHe+2 were also extremely sensitive to the ab initio ansatz by which they are modelled. The respective bonding of the H and He in both HMHe+ and HMHe2+ appeared to be charge-dependent in the case of Be, Mg and Ca. Despite the weak bonding observed for the Group-II hydrohelide and helide monocations, the corresponding dications each exhibit thermodynamically stable equilibria. The solution algorithm of von Nagy-Felsobuki and co-workers was employed in the calculation of vibrational and rovibrational spectra. This algorithm employed an Eckart-Watson Hamiltonian in conjunction with rectilinear normal co-ordinates. Vibrational and rovibrational Hamiltonian matrices were diagonalised using variational methods. This algorithm was extended so that the vibration transition moment integrals, and hence vibrational radiative properties, of linear triatomic molecules could be calculated. A method by which vibration-averaged structures are calculated was also developed and implemented. Analytical potential energy functions (PEFs) and dipole moment functions (DMFs) of (1A1)LiH+2, (1A1)NaH+2, (1A1)BeH2+2,(1A1)MgH2+2, (1Σ+g )BeHe2+2, (2Σ+)HBeHe2+, (1Σ+g )MgHe2+2 and (2Σ+)HMgHe2+ were developed using leastsquare regression techniques in conjunction with discrete ab initio grids. Vibrational structures and spectra of these species were subsequently calculated. In addition, the rovibrational spectra of (1A1)LiH+2, (1A1)NaH+2, (1A1)BeH2+2 and (1A1)MgH2+2 were calculated. For (1A1)LiH+2 and (1A1)LiD+2 , calculated rovibrational transition frequencies for J ≤ 10 and 0 ≤ K ≤ 3 were within ca. 0.1-0.2% of experimental values.
7

Ab Initio investigation of the electronic structure and rovibrational spectroscopy of group-I and II metal hydrides and helides

Page, Alister J. January 2008 (has links)
Research Doctorate - Doctor of Philosophy (PhD) / (**Note: this abstract is a plain text version of the author's abstract, the original of which contains characters and symbols which cannot be accurately represented in this format. The properly formatted abstract can be viewed in the Abstract and Thesis files above.**) The electronic structure and rovibrational spectroscopy of MH2, MHn+2, HMHen+ and MHen+2 (M = Li, Be, Na, Mg, K, Ca; n = 1, 2) have been investigated using correlated ab initio ansatz. In order to determine the efficacy of various electronic structure methods with respect to Group-I and II hydrides and helides, atomic properties of Li, Be,Na, Mg, K and Ca were calculated. Relativistically-corrected UCCSD(T) and ICMRCI(+Q) were deemed to be the most suitable ansatz with respect to both efficiency and accuracy. The lowest 2A1 and 2Σ- states of MH2 were found to be purely repulsive, in agreement with previous predictions. The main factor determining the structure and stability of the excited states of MH2 was the relative orientations and occupations of the valence p atomic orbital of M and the H2 1Ou orbital. The ground states of MHn+2 were found to be the result of the charge-quadrupole interaction between Mn+ and the H2 molecular subunit. The structures of the ground states of HMHe+ were extremely uxional with respect to the central bond angle co-ordinate. The ground state PESs of MHe+2 were also extremely sensitive to the ab initio ansatz by which they are modelled. The respective bonding of the H and He in both HMHe+ and HMHe2+ appeared to be charge-dependent in the case of Be, Mg and Ca. Despite the weak bonding observed for the Group-II hydrohelide and helide monocations, the corresponding dications each exhibit thermodynamically stable equilibria. The solution algorithm of von Nagy-Felsobuki and co-workers was employed in the calculation of vibrational and rovibrational spectra. This algorithm employed an Eckart-Watson Hamiltonian in conjunction with rectilinear normal co-ordinates. Vibrational and rovibrational Hamiltonian matrices were diagonalised using variational methods. This algorithm was extended so that the vibration transition moment integrals, and hence vibrational radiative properties, of linear triatomic molecules could be calculated. A method by which vibration-averaged structures are calculated was also developed and implemented. Analytical potential energy functions (PEFs) and dipole moment functions (DMFs) of (1A1)LiH+2, (1A1)NaH+2, (1A1)BeH2+2,(1A1)MgH2+2, (1Σ+g )BeHe2+2, (2Σ+)HBeHe2+, (1Σ+g )MgHe2+2 and (2Σ+)HMgHe2+ were developed using leastsquare regression techniques in conjunction with discrete ab initio grids. Vibrational structures and spectra of these species were subsequently calculated. In addition, the rovibrational spectra of (1A1)LiH+2, (1A1)NaH+2, (1A1)BeH2+2 and (1A1)MgH2+2 were calculated. For (1A1)LiH+2 and (1A1)LiD+2 , calculated rovibrational transition frequencies for J ≤ 10 and 0 ≤ K ≤ 3 were within ca. 0.1-0.2% of experimental values.
8

Complexidade da farmacoterapia: perfil farmacoterapêutico e desfechos associados / Medication regimen complexity: pharmacoterapeutical profile and associated outcomes

Conceição, Vanessa Alves da 21 February 2018 (has links)
Coordenação de Aperfeiçoamento de Pessoal de Nível Superior - CAPES / Introduction. Aging favors the appearance of propitious clinical conditions to a high use of medicines, a reality in the elderly over 65 years of age. However, the number of medicines used should not be the only predictor of a medication regimen complexity, other factors may increase the complexity of pharmacotherapy leading to possible problems related to pharmacotherapy. In this perspective, there are few national studies that evaluate the medication regimen complexity in the elderly, especially those that evaluate outcomes influenced by this complexity, so as to allow interventions for its optimization. Thus, the objective of this dissertation was to evaluate the pharmacotherapeutic profile and the health outcomes associated with the medication regimen complexity. Methods. This study was carried out in two stages. In the first stage, a descriptive cross-sectional study was performed to evaluate the medication regimen complexity of elderly patients in three long-term care facilities using the Medication Regimen Complexity Index (MRCI). This study was conducted for 12 months in three long-term care facilities in the state of Sergipe. In the second stage, a systematic review was performed to identify in the literature which outcomes were influenced by the medication regimen complexity, using the MRCI. We analyzed all study designs published until February 2017 who met the following eligibility criteria: using the MRCI instrument to measure the medication regimen complexity, assessing the medication regimen complexity for global regimens, related the medication regimen complexity with clinical and/or humanistic and/or economic outcome, was written in English, Spanish or Portuguese. Results. In the first stage, the evaluation of the medication regimen complexity obtained an average of 15.1 points (± 9.8), with a minimum of two and a maximum of 59 points. The highest levels of complexity were associated with the dose frequency, with a mean of 5.5 (± 3.6) points. A significant relationship between the medication regimen complexity and the variables polypharmacy, drug interaction, drug potentially inappropriate for the elderly and therapeutic duplicity was found (p <0.001). In the second stage, of the 610 studies evaluated, 20 met the eligibility criteria. The health outcomes most influenced by the medication regimen complexity were the clinical outcomes: hospitalization, hospital readmission and adherence to pharmacotherapy, most of the studies presented satisfactory results to association the outcomes with the complexity and obtained good methodological quality. Conclusion. This dissertation made it possible to evaluate the pharmacotherapeutic profile of elderly patients, showed that besides polypharmacy, potential drug interaction, therapeutic duplicity and potentially inappropriate medicines for the elderly are risk factors for the increased medication regimen complexity in these patients. Furthermore, identified that the health outcomes most influenced by the medication regimen complexity were ones clinical: hospitalization, hospital readmission and adherence to the pharmacotherapy. / Introdução. O envelhecimento favorece o aparecimento de condições clínicas propícias para o elevado uso de medicamentos, observado principalmente em pacientes acima de 65 anos de idade. Entretanto, o número de medicamentos utilizados não deve ser o único preditor de uma farmacoterapia complexa, pois outros fatores podem elevar a complexidade, conduzindo a possíveis problemas relacionados à farmacoterapia. Nesta perspectiva, são escassos os estudos nacionais que avaliam a complexidade da farmacoterapia em idosos, principalmente os que analisam desfechos influenciados por essa complexidade, de modo a permitir intervenções para sua otimização. Assim, o objetivo desta dissertação foi avaliar o perfil farmacoterapêutico e os desfechos em saúde associados à complexidade da farmacoterapia. Metodologia. Este estudo foi realizado em duas etapas. Na primeira, foi realizado um estudo transversal descritivo para avaliar a complexidade da farmacoterapia de idosos atendidos em três instituições de longa permanência para idosos (ILPIs), por meio do instrumento Medication Regimen Complexity Index (MRCI). Este estudo foi conduzido por 12 meses em três instituições no Estado de Sergipe. Na segunda etapa, foi realizada uma revisão sistemática, a fim de identificar, na literatura, quais desfechos estão associados à complexidade da farmacoterapia, medida pelo instrumento MRCI. Foram analisados todos os delineamentos de estudos publicados até fevereiro de 2017 que atenderam aos seguintes critérios de elegibilidade: usar o instrumento MRCI para medir a complexidade da farmacoterapia; avaliar a complexidade da farmacoterapia para os regimes globais dos pacientes; e relacionar a complexidade da farmacoterapia com desfechos clínicos e/ou humanísticos e/ou econômicos, publicados em inglês, espanhol ou português. Resultados. Na primeira etapa, a avaliação da complexidade da farmacoterapia obteve média de 15,1 pontos (± 9,8), com mínimo de dois e máximo de 59 pontos. Os níveis mais altos de complexidade foram associados à frequência de dose, com uma média de 5,5 (± 3,6). Além disso, foi identificada relação significativa entre a complexidade da farmacoterapia e as variáveis polifarmácia, interação medicamentosa, medicamento potencialmente inapropriado para idosos e duplicidade terapêutica (p< 0,001). Na segunda etapa, dos 610 estudos avaliados, 20 preencheram os critérios de elegibilidade. Os desfechos em saúde mais influenciados pela complexidade da farmacoterapia foram os desfechos clínicos: hospitalização, readmissão hospitalar e adesão à farmacoterapia. A maioria dos estudos apresentou resultados satisfatórios para associação dos desfechos com a complexidade e obtiveram boa qualidade metodológica. Conclusão. Esta dissertação possibilitou avaliar o perfil farmacoterapêutico de pacientes idosos e identificar que, além da polifarmácia, interação medicamentosa potencial, duplicidade terapêutica e medicamentos potencialmente inapropriados para idosos são fatores de risco para o aumento da complexidade da farmacoterapia nestes pacientes. Além disso, identificou-se que os desfechos em saúde mais influenciados pela complexidade da farmacoterapia foram os clínicos: hospitalização, readmissão hospitalar e adesão a farmacoterapia. / Aracaju, SE

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