Browsing by Author "Munoz-Castro, Alvaro"
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- ItemElectronic pathway of the exciplex emitters. Unraveling the emission properties from theoretical calculations(2024) Claveria-Cadiz, Francisca; Rojas-Poblete, Macarena; Munoz-Castro, Alvaro; Schott, Eduardo; Guajardo-Maturana, RaulMost emissive materials have become significant research findings for building organic light-emitting diode (OLED) devices. Prominent organic electronics reach applications such as displays, lighting, and photodynamic therapy, among others. Thus, the area of organic emitters has rapidly developed thanks to the synergy between theoretical and experimental works. Here, organic emitters are accurately studied, describing their electronic structure, including the electronic transitions, excited state energies, and coupling characteristics. Consequently, a tandem of methodologies, such as density functional theory (DFT) and time-dependent density functional theory (TDDFT), besides the MDReaxFF simulations, were employed. Therefore, we focus on exciplex emitters reported as donating-accepting to describe the photophysical process contained in such emitters, establishing electron hopping rates from the monomer and dimeric conformations and assessing the singlet and triplet states. The evaluations of electronic coupling and the reorganization energy (lambda) enable the accurate computing of crossing hopping for dimer and free dyes, proposing a reliable scheme of charge transfer properties. These findings bear a novel strategy for studying OLED devices and pave the way for developing more environmentally friendly technologies.
- ItemHeterobinuclear s-Indacene Rhodium Complexes: Synthesis and Characterization(2009) Adams Wrighton, Christopher William; Morales Verdejo, César Aarón; Morales Cárdenas, Verónica; MacLeod-Carey, Desmond; Manríquez M., Juan Manuel; Chávez Madariaga, Ivonne; Munoz-Castro, Alvaro; Delpech, Fabien; Castel, Annie; Gornitzka, Heinz; Riviere-Baudet, Monique; Riviere, Pierre; Molins, Elies
- ItemHeterobinuclear s-Indacene Rhodium Complexes: Synthesis and Characterization (pg 784, 2009)(2009) Adams Wrighton, Christopher William; Morales Verdejo, César Aarón; Morales Cárdenas, Verónica; MacLeod-Carey, Desmond; Manríquez M., Juan Manuel; Chávez Madariaga, Ivonne; Munoz-Castro, Alvaro; Delpech, Fabien; Castel, Annie; Gornitzka, Heinz; Riviere-Baudet, Monique; Riviere, Pierre; Molins, Elies
- ItemNew mono and bimetallic iron complexes derived from partially methylated s-indacene. Evidence of a trinuclear iron s-indacene complex(2014) Morales-Verdejo, Cesar; Martinez-Diaz, Ivan; Adams, Christopher; Araneda, Juan Felipe; Oehninger, Luciano; Carey, Desmond Mac-Leod; Munoz-Castro, Alvaro; Arratia-Perez, Ramiro; Chavez, Ivonne; Manuel Manriquez, JuanThe preparation and characterization of new mono- and multinuclear iron complexes derived from s-indacene partially alkylated has been achieved by the development of rational synthetic routes. The synthesis of the new multimetallic complexes are based on the employment of 1,5-dihydro-2,4,6, 8-tetramethyl-s-indacene (Ic'H-2) as ligand to obtain two monometallic complexes, namely, [Cp*-Fe-(eta(5)-2,4,6,8-tetramethyl-5-hydro-s-indacenide)] (1), and [Fe-bis(eta(5)-2,4,6,8-tetramethyl-5-hydro-s-indacenide)] (2) (Cp* = pentamethylcyclopentadiene), as well as, the new bimetallic [Cp*Fe-(mu:eta(5):eta(5)-2,4,6,8-tetramethyl-s-indaceneiide)-FeCp*] (3) and trimetallic [Fe-bis{Cp*Fe-(mu:eta(5):eta(5)-2,4,6,8-tetramethyl-s-indaceneiide)}] (4) complexes. All complexes here reported were characterized by means of H-1, C-13 NMR, mass spectrometry, elemental analysis, together with cyclic voltammetry. In addition, these complexes have been studied by DFT methods in order to gain further knowledge about its electronic structure. In addition, the possibility to generate organometallic polymers employing the complexes here reported, is proposed theoretically with the study of an oligomer titled as [Cp*(Fe(Ic')}(4)FeCp*], 6(t). (C) 2013 Elsevier Ltd. All rights reserved.
- ItemOn the cation- capabilities of small all sp2-carbon host structures. Evaluation of [6.8]3cyclacene from relativistic DFT calculations(2019) Ortolan, Alexandre O.; Charistos, Nicholas D.; Guajardo-Maturana, Raul; Olea Ulloa, Carolina; Caramori, Giovanni F.; Parreira, Renato L. T.; Munoz-Castro, AlvaroCation- interactions are noncovalent forces with essential roles in the stability of protein structures, molecular recognition, and host-guest chemistry. In this work, we discuss the formation of cation- complexes involving one of the smallest characterized nanobelts to date, given [6.8](3)cyclacene, by using relativistic DFT-D calculations. Such nanobelt exhibits a noteworthy all-sp(2) carbon backbone, leading to a rigid and confined host framework. Our results reveal that the inclusion of representative cations, such as Ag+ and Sn2+, appears to be plausible, revealing that it is feasible to obtain these compounds experimentally. Such systems involves two contrasting coordination modes, where the Ag+ cation remains coordinated in the upper face of the nanobelt, whereas the Sn2+ is able to be located at the center of the structure. In addition, the coordination of isoelectronic Cd2+ and In+ was also discussed. Moreover, the bonding characteristics of the resulting cation- interaction show that the -orbitals from the nanobelt 1 are able to moderate the charge transfer, according to the selected cation, which can be seen as an interesting strategy to tune the amount of charge of the -backbone in nanobelts. We envisage that the use of more rigid host in the formation of cation- interactions will be beneficial to gain a better understanding about the metal coordination and also to tune the capabilities of related nanobelts or nanotubes sections.
- ItemStructural, electronic and magnetic properties of copper(I) cubic clusters(2021) Barboza, Cristina A.; Gambetta, Adrian; Arratia-Perez, Ramiro; Rodriguez-Kessler, Peter L.; Munoz-Castro, Alvaro; MacLeod-Carey, DesmondWe report the molecular and electronic structure, and the calculated electronic excitation energies, using the time dependent density functional methodologies (TD-DFT), and the induced magnetic field (B-i) of a series of Cu(I) dithiolato and diselenolato species of formula [Cu-8(L)(6)]. They are composed by eight copper atoms forming a Cu-8 cube and six bidentate ligands (L), where twelve chalcogen atoms (Q) bridging the edges of the copper cube, in such a way that chalcogen atoms describe an icosahedron, enclosing a cubic [Cu8(mu-Q(12))](4) core of T-h symmetry. The Q...Q bite distance is similar in all clusters, without being influenced by the Cu-Cu distance, suggesting the existence of metallophilic interactions that stabilize the cluster structure. Despite of the structural similarities, the electronic structure of these clusters present some differences which are magnified on their optical properties. Excitation energies and their composition depend on the nature of each different ligand in these clusters, according to CT(lambda(M) )index to determine the ligand to metal (LM) or metal to ligand charge transfer (MLCT) character of each calculated electronic transition. The magnetic properties calculations show the importance to separate the magnetic response into their individual components (B-i with i = x, y, z, iso), and diamagnetic and paramagnetic contributions to understand the differences according to the type of ligand on the cluster structure. (C) 2020 Elsevier Ltd. All rights reserved.
- ItemTheoretical insights into the adsorption of neutral, radical and anionic thiophenols on gold(111)(2013) Miranda-Rojas, S.; Munoz-Castro, Alvaro; Arratia-Perez, Ramiro; Mendizabal, FernandoThe interaction of thiol and thiolate containing molecules with gold (S-Au) has gained increasing interest because of its applications in molecular electronic devices and catalysis. In this context, the enhanced conductivity of thiophenol compared to alkanethiol represents an opportunity to develop more sensitive and selective gold-based devices by incorporating molecules with the aryl-thiol moiety into their structures. As has been proposed earlier, the thiol moiety is deprotonated after binding to gold, hence, we present here a comparative study of the S-Au bond strength between several neutral and deprotonated aromatic-sulfur systems in their anionic and radical forms with a detailed description of the nature of this interaction. The study was performed by means of computational chemistry methods, using a cluster of 42 Au atoms as a model of the Au(111) surface that allowed us to provide new chemical insights to control the S-Au interface interaction strength. Our results revealed that the thiophenols-gold interaction is mainly dispersive where the interaction energies range between 31 and 43 kcal mol(-1). The radical and anionic thiophenolates-gold interaction increases due to a strong charge transfer character, depicting interaction energies in the range of 50 to 55 kcal mol(-1) and 62 to 92 kcal mol(-1), respectively. These results suggest that for the anionic thiophenolate the binding strength can be tailored according to the electron-donor capabilities of the ligand which in turn can be finely tuned by several substituents. Our results are of possible impact for the design of new devices.