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Esta tese apresenta uma nova aproximação variacional baseada no Método da Coordenada Geradora e na Teoria do Funcional da Densidade. Nesta nova aproximação, a função de onda de muitos corpos é representada como uma superposição de determinantes de Slater Kohn-Sham não-ortogonais calculados a partir de Hamiltonianos diferentes que carregam uma coordenada geradora atuando como parâmetro de deformação. A discretização integral sobre o conjunto de coordenadas geradoras fornece a energia total variacional do sistema e a contribuição de cada determinante na combinação da respectiva função de onda de muitos corpos. A flexibilidade desta nova metodologia permitiu aplicá-la no estudo das energias totais do estado fundamental e excitado dos átomos da série isoeletrônica do Hélio, utilizando diferentes conjuntos de coordenadas geradoras, diferentes aproximações para o potencial de troca e correlação e diferentes maneiras de implementar a coordenada geradora dentro do Hamiltoniano Kohn-Sham. Em seguida, as bases desta nova metodologia foram estendidas para o caso dependente do tempo, permitindo estudar, por exemplo, processos não-lineares como excitações duplas, conhecidas por sua forte dependência dos efeitos de memória. A nova metodologia foi aplicada no estudo das oscilações paramétricas de um sistema de dois elétron sob um potencial harmônico, o átomo de Hooke. Os resultados demonstram que a escolha adequada das coordenadas geradoras reproduz com precisão os efeitos lineares e não-lineares dos elétrons do sistema que não podem ser descritos pela Teoria do Funcional da Densidade Dependente do Tempo utilizando a aproximação adiabática. Assim, a nova metodologia mostra-se: flexível, pois permite calcular propriedades do estado fundamental e excitado, estáticas e dinâmicas dos sistemas eletrônicos fornecendo ainda uma aproximação variacional para as respectivas funções de onda de muitos corpos em todos os casos; e também viável, pois fornece resultados promissores no caso independente do tempo constituindo uma ferramenta simples e computacionalmente barata de incluir os efeitos de memória em qualquer aproximação adiabática no caso dependente do tempo. / A new variational approach based on the Generator Coordinate Method and Density- Functional Theory is presented. It represents the interacting many-body wave function as a superposition of non-orthogonal Kohn-Sham Slater determinants arising from different Hamiltonians featuring a generator coordinate acting as a deformation parameter. An integral discretization procedure over the set of generator coordinates provides the variational total energy of the system and the weight of each determinant in the approximation of the respective interacting many-body wave functions. The method was used to calculate the ground and excited state total energies of the Helium isoelectronic serie of atoms using different sets of generator coordinates, different approximations to the exchange-correlation potential and different implementations of the generator coordinate whithin the Kohn-Sham Hamiltonian. Next, the time dependent extension of the method is presented allowing its application, for example, on the study of nonlinear processess as double excitations which are known to be strongly dependent of the memory effects. As an illustration, the method is sucessfully applied to driven parametric oscillations of a two interacting electrons in a harmonic potential, the Hooke\'s atom. It is demonstrated that a proper choice of time-dependent generator coordinates in conjunction with the adiabatic local-density approximation reproduces the exact linear and nonlinear twoelectron dynamics quite accurately, including features associated with double excitations that cannot be captured by Time-Dependent Density-Functional Theory in the adiabatic approximation. Therefore, the method is considered, flexible since it allows to calculate ground and excited-states, static and dynamic properties of the electronic systems yeilding a variational approach to the interacting many-body wave functions for all cases, and feasible, since it improves the results for ground and excited-states total energies in the time-independente case, besides to be a conceptually and computationally simple tool to build memory effects into any existing adiabatic exchange-correlation potential in the time-dependent case.

Absorção e Emissão de radiação eletromagnética por moléculas na região do UV-Vis fornece informações sobre os estados eletrônicos excitados, sendo propriedades de grande interesse devido a sua relação com processos biológicos, bem como suas possíveis aplicações em diagnósticos e tecnologia. Essas propriedades são sensíveis ao meio em que as moléculas se encontram, tornando-se assim natural a busca por métodos teóricos que possibilitam descrever essas interações. Neste trabalho, nós usamos a metodologia Sequential-Quantum Mechanics/Molecular Mechanics para estudar o espectro de absorção e de emissão de moléculas de relevância biológica, quando em solução. Simulações clássicas Monte Carlo foram usadas pra construir uma configuração eletrostática média do líquido para posterior cálculo das propriedades, feito através dos métodos multiconfiguracionais CASSCF e CASPT2. Cuidados especiais foram tomados para incluir a polarização eletrônica que o soluto sofre devido à presença do solvente. Nossa contribuição é a adaptação do método do Gradiente de Energia Livre para permitir a obtenção de geometrias de estados excitados do soluto em solução. A técnica foi implementada em um programa e aplicada com sucesso nos sistemas estudados. As perspectivas agora se abrem para a obtenção de intersecções cônicas em meio solvente, permitindo assim o estudo de decaimentos não-radiativos em sistemas solvatados. / Absorption and emission of electromagnetic radiation by molecules in the UV-Vis region yields information about the electronic excited states, being properties of great interest due its relation with biological process, as well as its possible applications in diagnostics and technology. These properties are sensible to the environment in which the molecules are, making natural the search for theoretical methods that describe these interactions. In this work, we have used the Sequential-Quantum Mechanics/Molecular Mechanics methodology to study the spectrum of absorption and emission of molecules of biological relevance, when in solution. Classical Monte Carlo simulations were carried out to construct an average solvent electrostatic configuration and used to represent the liquid in posterior quantum mechanics calculation of the properties, performed by using the multiconfigurational methods CASSCF and CASPT2. Special cares were taken to include the electronic polarization of the solute due the solvent. Our contribution is the adaptation of the Free Energy Gradient method to allow the determination of the solute excited states geometries in solution. The method was implemented in a computer program and successfully applied in the systems studied. The perspectives are now open to the calculation of conical intersection in solvent environment, enabling the study of nonradioactive decays in solvated systems.

La bioluminescence est un processus complexe dans lequel la réaction chimique d'un substrat, catalysée par une protéine, entraîne l'apparition d'une émission de lumière dans le spectre visible. Dans le cas des lucioles, un insecte émettant dans le domaine du jaune-vert, le substrat se nomme luciférine et la protéine luciférase. Cependant, la taille et la complexité de ce système chimique limite sa compréhension, notamment celle du mécanisme réactionnel.L'apport de la chimie théorique dans ce domaine est essentiel et a prouvé son utilité dans de nombreux cas. L'utilisation de la méthode QM/MM, méthode hybride couplant la mécanique quantique et la mécanique moléculaire permet de modéliser et d'étudier ces systèmes biologiques.Cette thèse se focalise sur deux approches différentes de l'étude de la bioluminescence chez les lucioles. La première consiste à étudier l'effet de certaines modifications chimiques sur la couleur de la bioluminescence. On s'intéresse plus particulièrement à un analogue de la luciférine et à certaines luciférases issues d'autres systèmes bioluminescents. Par cette étude on cherche à rationaliser et à prédire l'effet ainsi que l’impact de ces changements sur l’émission. Le deuxième sujet explore deux étapes du mécanisme réactionnel de la bioluminescence: d'une part, la coordination du dioxygène sur un intermédiaire de la réaction, une étape encore non étudiée et d'autre part la réaction de tautomérisation dans l'état excité et au sein de la protéine entre deux formes émissives possibles de la luciférine / The bioluminescence is a complex process that involves the reaction of a substrate, catalysed by an enzyme that sheds light in the visible spectra. In fireflies, the light emitted has a yellow-green tone thanks to the interaction between the substrate luciferin and the protein luciferase. However the size and the complexity of the system prevent its comprehension especially when dealing with the reaction mechanism.The use of computational chemistry is key to understand and improve the comprehension of the bioluminescence. The hybrid QM/MM method that combines quantum mechanics with molecular mechanics is a great tool to model and study bioluminescent systems.This thesis deals with two different approaches of the bioluminescence in fireflies. The first one is related to the study of chemical modifications that tune the emission colour. We will discuss about one analogue of the luciferin and on new luciferases from others bioluminescent species. The goals of this study are to rationalise and predict both the effect and the impact of these modifications on the emission. The second subject deals with two different steps of the bioluminescent mechanism. The first one discusses the binding of the dioxygen to the bioluminescent intermediate, which was so far unstudied and the second one about the tautomerization in the excited state and in the protein of two possible emissive forms of the luciferin

Submitted by Fabio Sobreira Campos da Costa (fabio.sobreira@ufpe.br) on 2017-08-01T13:42:24Z No. of bitstreams: 2 license_rdf: 811 bytes, checksum: e39d27027a6cc9cb039ad269a5db8e34 (MD5) JDiogo_Tese Final_Quimica.pdf: 8861608 bytes, checksum: b9ce8a33624820a531c0a5c298600d94 (MD5) / Made available in DSpace on 2017-08-01T13:42:24Z (GMT). No. of bitstreams: 2 license_rdf: 811 bytes, checksum: e39d27027a6cc9cb039ad269a5db8e34 (MD5) JDiogo_Tese Final_Quimica.pdf: 8861608 bytes, checksum: b9ce8a33624820a531c0a5c298600d94 (MD5) Previous issue date: 2017-01-26 / CNPQ / Metodologias te´oricas s˜ao ´uteis para complementar investigac¸˜oes experimentais e guiar novos experimentos envolvendo compostos luminescentes de lantan´ıdeos. A ausˆencia de uma ferramenta computacional contendo tais m´etodos motivou o desenvolvimento do LUMPAC. Se por um lado o LUMPAC difundiu o uso dessas metodologias, por outro as suas limitac¸˜oes tamb´em foram evidenciadas. Nesse sentido, pˆode-se conhecer melhor quais m´etodos merecem uma atenc¸˜ao especial, a saber: c´alculo dos parˆametros de intensidade (Ωλ), c´alculo da energia dos estados excitados dos ligantes e c´alculo da taxa de emiss˜ao n˜ao-radiativa (Anrad). O objetivo geral do presente trabalho de doutoramento consiste em corrigir algumas dessas limitac¸˜oes. Quantoaoc´alculodosΩλ,conseguimosatenuaroproblemacomumanovaformadeajustedos fatores de carga e das polarizabilidades atrav´es de um procedimento que foi denominado de Modelo da UnicidadeQDC, o qual faz uso de um conjunto bastante reduzido de parˆametros (Q,D eC). A importˆancia do ajusteQDC ´e que todas as quantidades derivadas se tornam tamb´em ´unicas para uma dada geometria do complexo, incluindo um esquema proposto de partic¸˜ao qu´ımico da taxa de emiss˜ao radiativa (Arad) em termos dos efeitos dos ligantes. Para demonstrar uma das poss´ıveis aplicac¸˜oes dessa partic¸˜ao, foi considerado o caso de complexos tern´arios de Eu3+ de ligantes n˜ao-iˆonicos repetidos e com os ligantes betadicetonatos DBM, TTA e BTFA. A partic¸˜ao ordenou perfeitamente a combinac¸˜ao n˜ao ´obvia de pares de ligantes n˜ao-iˆonicos que levam aos compostos misturados com os maiores valores deAexp rad. Quanto ao c´alculo dos estados excitados dos ligantes, ´e proposta uma parametrizac¸˜ao do m´etodo CIS baseadonaaproximac¸˜aoNDDO,exclusivamenteparasistemaslantan´ıdicos. Al´emdisso,realizamosumestudoavaliativodemetodologiasTDDFTaplicadasaoc´alculodeestadosexcitados de ligantes em complexos de lantan´ıdeos. Dentre os funcionais e func¸˜oes de base avaliados, a combinac¸˜ao LC-ωPBE/6-31G(d) foi aquela que forneceu as energias tripleto mais concordantes com os dados obtidos na literatura, sendo o erro m´edio absoluto correspondente em torno de 1600 cm−1. Atrav´es da parametrizac¸˜ao do modelo NDDO-CIS implementado no programa ORCA foi poss´ıvel obter um modelo semiemp´ırico para o c´alculo da energia tripleto de complexosdelantan´ıdeocom qualidade bem superiora da melhormetodologiaTDDFT avaliada. / Theoretical methodologies are useful to complement experimental investigations, and to guide new experiments involving luminescent lanthanide compounds. The lack of a software containing these methods motivated us to the development of the user friendly software package LUMPAC. And indeed, LUMPAC is slowly popularising the use of these theoretical methodologies - methodologies that are being put to more frequent tests, and are, consequently, slowly revealing their limitations. In this sense, we identified which aspects of the methods would deserve a more special attention, namely: intensity parameters calculations (Ωλ), calculation of the excited state energies of the ligands, and the calculation of the non-radiative decay rate (Anrad). The overall objective of this doctoral work is to correct some of these limitations as wellastoadvancenewdevelopments. RegardingtheΩλ calculation,wemitigatedthisproblem with a new way to adjust the charge factors and polarizabilities through a procedure we called theQDC Uniqueness Model, which makes use of a fairly small set of adjustaeble parameters (Q,D, andC). The importance of theQDC adjustment is that all derived quantities become also unique for a given complex geometry, including the chemical partition of the radiative emission rate (Arad) in terms of the effects of the ligands, which is being advanced here. To demonstrate one of the possible applications of this chemical partition, we address the case of repeating non-ionic ligand ternary complexes of europium(III) with DBM, TTA, and BTFA. The chemical partition perfectly ordered the non-obvious combination of pairs of non-ionic ligands that led to the mixed ligand compounds with the highest values ofAexp rad . Regarding the calculation of the excited states of the ligands, a new parametrization of the CIS method based on the NDDO approximation is being proposed, exclusively for lanthanide complexes. In addition, we carried out a study to evaluate some TDDFT methodologies for the calculation of excited states of ligands in lanthanide complexes. Among the functionals and basis sets evaluated, the combination LC-ωPBE/6-31G(d) was the one that led to the lowest UME (unsigned mean error), of around 1600 cm−1, for the triplet energies in comparison with data from the literature. The parametrization of the NDDO-CIS model implemented into ORCA provided a semiempirical method for the triplet energy calculation of lanthanide complexes with better predictionpower thanthebestassessed TDDFT method.

L'un des principaux défis de la physique nucléaire moderne est de comprendre la structure nucléaire des éléments les plus lourds. Les barrières de fission calculées dans le modèle de la goutte liquide macroscopique ne parviennent pas à expliquer la stabilité des noyaux avec un nombre de protons Z≥90. Cette barrière disparaît pour les éléments transfermium (Z≥100) qui ne sont donc stabilisés que par des effets quantiques de couche. Les noyaux lourds sont un laboratoire unique pour étudier l'évolution de la structure nucléaire dans des conditions extrêmes de masse et de champ Coulombien. Bien que de nombreuses théories s’accordent sur l'existence d’un « îlot de stabilité », les prédictions sur son emplacement exact en terme de nombre de protons et neutrons varient grandement. Les études expérimentales des noyaux transfermium s’avèrent donc essentielles pour contraindre les modèles théoriques et mieux comprendre l’évolution des couches nucléaires.L'interaction entre le mouvement des particules individuelles et les degrés de liberté collectifs du noyau a été investiguée dans le 251Fm par le biais de la spectroscopie combinée délectrons de conversion interne et de photons γ. Les états excités du 251Fm ont été peuplés dans la décroissance α du 255No, produit dans les 2 réactions suivantes: 208Pb(48Ca, 1n)255No et 209Bi(48Ca, 2n)255Lr. Les expériences ont été réalisées au JINR, FLNR, Dubna. Les faisceaux intenses ont été délivrés par le cyclotron U-400, et les séparateurs VASSILISSA ou SHELS ont été utilisés pour sélectionner les résidus de fusion-évaporation. Le spectromètre GABRIELA a été utilisé pour effectuer des mesures des propriétés de décroissance caractéristique corrélées en temps et en position pour isoler les noyaux d'intérêt. La spectroscopie d'électrons de conversion interne du 251Fm a été réalisée pour la première fois. Ces mesures ont permis d'établir les multipolarités de plusieurs transitions et de quantifier le rapport de mélange M2/E3 dans la désintégration de l'isomère 5/2+. Le B (E3) valeur extraite est comparée à celles des autres membres de la chaîne isotonique N=151 et les calculs QRPA utilisant l'interaction effective de Gogny.Au cours de ce travail, une nouvelle méthode graphique d’extraction des rapports de mélange de transitions nucléaires a été développé. Cette méthode intuitive et illustrative et ses limites d'application, ainsi que certains aspects du calcul des rapports de mélange au-delà de ces limites, sont décrites et discutées.Les détecteurs silicium double-face à strips (DSDS) sont largement utilisés en spectrométrie nucléaire, en particulier au plan focal de séparateurs pour détecter l'implantation et la désintégration ultérieure des noyaux les plus lourds. Il a été constaté que la présence de strips mécaniquement déconnectés sur une face du DSDS peut conduire à l'apparition de pics d'énergie abaissée sur la face opposée en raison de la variation de la capacité totale. Cet effet, ainsi que les méthodes de correction du spectre, ont été étudiés et discutés. L'utilisation de simulations GEANT4 pour résoudre les effets de sommation α-ECI dans le DSDS et pour contraindre les coefficients de conversion interne des transitions impliquées dans la désexcitation du noyau d’intérêt est présentée à l’aide de l’exemple du 221Th.Une bonne partie des travaux ont été consacrés à la R&D pour un nouveau système électronique numérique pour le spectromètre GABRIELA et aux tests comparatifs de plusieurs cartes d'acquisition numériques. Les résultats de ces tests, ainsi que les algorithmes de traitement numérique du signal mis en œuvre pour une analyse non biaisée hors ligne sont présentés. / One of the major challenges of modern nuclear physics is to understand the nuclear structure of the heaviest elements. Fission barriers calculated within the macroscopic liquid drop model fail to explain the stability of nuclei with a number of protons Z≥90. Transfermium elements (Z≥100) have a vanishing liquid-drop barrier and are solely stabilized by quantum shell effects. They provide a unique laboratory to study the evolution of nuclear structure under the extreme conditions of large mass and strong Coulomb force. Though many theories agree on the existence of an “Island of Stability”, the predictions on its exact location in terms of number of protons and neutrons vary greatly. Hence the systematic study of transfermium nuclei is essential to constrain theoretical models and to get a better understanding of the evolution of nuclear shells.The interplay between single-particle and collective degrees of freedom in 251Fm was investigated by means combined internal conversion electron (ICE) and γ-ray spectroscopy. Excited states in 251Fm were populated via the α-decay of 255No produced in the two following fusion-evaporation reactions: 208Pb(48Ca, 1n)255No and 209Bi(48Ca, 2n)255Lr. The experiments were performed at the FLNR, JINR, Dubna. The intense beams were delivered by the U-400 cyclotron and the separators VASSILISSA or SHELS were used to select fusion evaporation residues. At their focal planes the GABRIELA spectrometer was used to perform a time and position correlated measurement of the characteristic decay properties to further isolate the nuclei of interest. ICE spectroscopy of 251Fm was performed for the first time. These measurements allowed to establish the multipolarities of several transitions in 251Fm and to quantify the M2/E3 mixing ratio in the decay of the low-lying 5/2+ isomer. The extracted B(E3) value is compared to those found in other members of the N=151 isotonic chain and to the QRPA calculations using the Gogny effective interaction.During this work, a novel graphical method of extracting mixing ratios for nuclear transitions has been developed. This intuitive and illustrative method and it’s limits of applicability, as well as certain aspects of the calculation of mixing ratios beyond these limits, are described and discussed.Double-sided silicon strip detectors (DSSD) are widely used in nuclear spectrometry, in particular at the focal plane of separators to detect the implantation and subsequent decay of the heaviest nuclei. It was found that the presence of mechanically disconnected strips on one face of the DSSD may lead to the occurrence of lower energy peaks on the opposite face due to the change of the total capacitance. This effect, along with the methods of restoring the correct spectra, has been studied and discussed. The use of GEANT4 simulations for resolving α-ICE summing in the DSSD and for constraining the internal conversion coefficients of the transitions involved in the decay of the nucleus of interest is presented with the example of 221Th.A significant part of the thesis work was dedicated to the R&D for a new digital electronics system for the GABRIELA spectrometer and to the comparative tests of several digital acquisition cards. The results of these tests, as well as the digital signal processing algorithms implemented for an unbiased off-line analysis are presented.

The GERDA experiment is searching for the neutrinoless double beta (0vbb) decay of Ge-76. By that, it tries to answer two long standing questions about the neutrino: 'How large is the neutrino mass?' and 'Is the neutrino either Dirac or Majorana particle?'. Additionally, an observation would imply that lepton number is not conserved, which is an important puzzle piece for theories explaining the asymmetry between matter and anti-matter in the universe. The effective Majorana electron neutrino mass can be extracted from the half-life of the 0vbb -decay. However, during that conversion large uncertainties are added through nuclear matrix elements, that are calculated by a variety of theoretical models. Experimental input is required to constrain such models and their parameters to improve the reliability of the calculations. Additional input can be obtained by comparing the model predictions for the two neutrino double beta (2vbb) decay to the ground state, but also for decay modes to excited states of the daughter nuclide with measurements. The latter decay modes have not yet been observed in the case of Ge-76. The event signature of transitions to excited states is enhanced by de-excitation gamma-rays. The GERDA experiment employs an array of bare germanium semi-conductor detectors in a liquid argon cryostat. This array is suited to search for excited state transition in the 2vbb and 0vbb -decay modes using data with coincident energy depositions in multiple detectors. This work presents the preparation and characterisation of this data set, which includes the evaluation and correction of crosstalk between detector channels, the determination of the energy resolution of the detectors and the modelling of background. In an analysis combining 22 kgyr of Phase I data with the first 35 kgyr of Phase II data of GERDA, no signal has been observed for 2/0vbb -decays of Ge-76 to the energetically lowest three excited states in Se-76. New limits have been set for the two neutrino decay modes at T1/2(2v)(0+g.s. to 0+1) > 3.1x10^23 yr, T1/2(2v)(0+g.s. to 2+1) > 3.4x10^23 yr T1/2(2v)(0+g.s. to 2+2) > 2.5x10^23 yr with 90% credibility using a Bayesian approach, improving upon the limits obtained in Phase I. The corresponding sensitivities are 3.6x10^23 yr, 6.7x10^23 yr and 3.7x10^23 yr, respectively. First limits are set for the neutrinoless decay modes in the order of (10^24-10^25) yr. Reaching the desired Phase II exposure of 100 kgyr, the sensitivities will increase by up to 50%.

<p>  Based on the multichannel quantum defect method and streamlined R-matrix treatment, this thesis studies the multi-photon ionization spectrum for atomic helium and barium, and explores the electronic correlations of these atoms. For the helium atom, the above-threshold-ionization spectra have been calculated, with two linearly polarized photons, two oppositely circularly polarized photons, and three linearly polarized photons. The propensity rules for the single-photon ionization and autoionizing decay have been extended into the multi-photon region, showing that the excitation rules are not always satisfied for the most prominent channel. In a separate project, based on the spontaneous two-photon decay of the helium 1s2s 1Se excited state that has a rather long lifetime, one can create photon pairs that are entangled in time, frequency, and polarization. Experimental schemes are proposed to use them as a laser source to ionize another helium. Finally, we considered the oneand two-photon pathway coherent control of atomic helium and barium near their autoionizing levels. For the helium atom, we proposed a controlling scheme that can flip 90 % of the photocurrent by a slight change of laser frequency. For the barium atom, we computed the phase lag between 6s1/2 and 5d3/2 ionization continua, which agrees with the experimental results that a previous phenomenological model failed to reproduce. Our treatment also develops formulas to describe the effects of hyperfine depolarization on multiphoton ionization processes, and it identifies resonances that had not been observed and classified in previous experiments. <br>  </p>

Previous work was successful at delineating reaction pathways for the photoactivated synthesis of an amine, [CztBu(PyriPr)(NH2−PyriPr)], by double intramolecular C−H activation and functionalization via irradiating a metal(II) azido complex, [CztBu(PyriPr)2NiN3. The present work seeks to expand upon earlier research, and to substitute the metal with iron or cobalt, and to expand the study to photocatalyzed intermolecular C−H activation and functionalization of organic substrates. Density functional theory (DFT) – B3LYP/6-31+G(d') and APFD/Def2TZVP – and time-dependent density functional theory (TDDFT) were used to propose a detailed pathway comprised of intermediates of low, intermediate, or high spin multiplicity and photo-generated excited states for the reaction of the azido complex, [CztBu(PyriPr)2MN3] to form the amine complex [CztBu(PyriPr)M(NH2−PyriPr)], M = Co, Ni or Fe, and the intermediates along the reaction pathway. For applications on quantum computing, the photophysical properties of photoactive d8 nickel(II) complexes are modeled. Such systems take advantage of a two-level system pathway between ground to excited state electronic transitions and could be useful for the discovery of successful candidates for a room temperature qubit, the analogue of a classical computational bit. A modified organometallic model, inspired by a nitrogen vacancy selective intersystem crossing model in diamond, was developed to take advantage of the formation of excited states. Tanabe-Sugano diagrams predict areas where these excited states may relax via phosphorescent emission. Under Zeeman splitting, these transitions create the conditions required for a two-level system needed to design a functional organometallic qubit.

No description available.