Molecular Orbitals
Mostrando 1-12 de 55 artigos, teses e dissertações.
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1. A New Synthetic Route and Comprehensive Topological Study of a Benzimidazole Derivative
Benzimidazole and its derivatives are molecules that have diverse biological properties, therefore we synthesized and studied a new benzimidazole to understand their physical/chemical properties. The compound was obtained through a new synthetic route, using graphite oxide, in the absence of solvent, with crystalline packaging supported by C-H…N and C-H…
Journal of the Brazilian Chemical Society. Publicado em: 2022
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2. Synthesis and Molecular Modeling Study of Two Bromo-Dimethoxybenzaldehydes
This work describes the synthesis, molecular structure, and packaging of the compounds 6-bromo-2,3-dimethoxybenzaldehyde (6-BRB) and 5-bromo-2,3-dimethoxybenzaldehyde (5 BRB). Characterization in the solid-state was carried out by X-ray diffraction, and the analysis of the interactions was described by the Hirshfeld surface, which helps in understanding the
Journal of the Brazilian Chemical Society. Publicado em: 2022
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3. Through-Bond and Through-Space Interactions in [2,2]Cyclophanes
The interpretation of the distortions of the electron distribution in [2,2]cyclophanes (22-CPs) is controversial. Some studies indicate that there is an accumulation of electron density (ρ) outside the cavity of 22-CPs. The nature of through-space (ts) interaction is still under debate. The relative importance of ts and through-bond (tb) is an open question
J. Braz. Chem. Soc.. Publicado em: 2021-07
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4. ORBITALS IN GENERAL CHEMISTRY, PART II: MATHEMATICAL REALITIES
In Part II of a three-part series, we discuss two factors absent from textbooks of general chemistry that are important in a discussion of teaching orbitals. First, atomic orbitals are shown systematically to comprise algebraic formulae in coordinates of not one but four sets (spherical polar, paraboloidal, ellipsoidal, spheroconical coordinates). Each formu
Quím. Nova. Publicado em: 2021-03
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5. HPV infection - Screening, diagnosis and management of HPV-induced lesions
In Part II of a three-part series, we discuss two factors absent from textbooks of general chemistry that are important in a discussion of teaching orbitals. First, atomic orbitals are shown systematically to comprise algebraic formulae in coordinates of not one but four sets (spherical polar, paraboloidal, ellipsoidal, spheroconical coordinates). Each formu
Rev. Bras. Ginecol. Obstet.. Publicado em: 2021-03
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6. ORBITALS IN GENERAL CHEMISTRY, PART I: THE GREAT DEBATE
In Part I of a three-part series, we present an objective survey of the technical literature discussing the inclusion of orbitals in high-school and post-secondary general chemistry. We start with the definition of orbitals. The presentation of orbitals in secondary (high) school is presented with arguments for and against. The content of orbitals in the cur
Quím. Nova. Publicado em: 2021-02
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7. RAMAN STUDIES OF BIS(PHENYLTERPYRAZINE)IRON(II) AND SUPRAMOLECULAR SPECIES WITH PENTACYANIDOFERRATE(II) IONS
The chemistry and spectroscopy of the iron(II) phenylterpyrazine complex, [Fe(phtpz)2]2+, were investigated in comparison with the analogous phenylterpyridine species, Fe(phtpy)2]2+, and the results indicated a strong electronic delocalization on the Fe(II) terimine chromophore encompassing the lateral pyrazyl groups. The delocalized nature of the molecular
Quím. Nova. Publicado em: 05/12/2019
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8. THEORETICAL STUDIES ON THE NEW HIGH-NITROGEN EXPLOSIVES N14 AND N18
The power of a compound is enhanced by the direct connection of nitrogen atoms, and its stability can be improved through conjugated structure. So novel high energy density materials N14 (1,6-dihydro-1,2,3,3a,4,5,5a,6,7,8,8a,9,10,10a-tetradecazapyrene) and N18 (1,2,2a,3,4,4a,5,6,6a,7,8,8a,9,10,10a,11,12a-octadecazacoronene) were designed, and their structure
Quím. Nova. Publicado em: 21/10/2019
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9. Benzodioxol Group Driving Supramolecular Arrangement of Two Tri-Methoxy Chalcones onto Β-Secretase 1 Enzyme Active Site
Chalcones are compounds with wide interesting biological activities including Alzheimer’s disease. A comparative study was performed between the chalcones (E)-1-(2-aminophenyl)-3-(3,4,5-trimethoxyphenyl)prop-2-en-1-one and 1-(6-amino-1,3-benzodioxol-5-yl)-3-(3,4,5-trimethoxyphenyl)prop-2-en-1-one regarding the influence of benzodioxol group on their molecu
J. Braz. Chem. Soc.. Publicado em: 16/09/2019
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10. HYBRID ATOMIC ORBITALS IN ORGANIC CHEMISTRY. PART 2: CRITIQUE OF PRACTICAL ASPECTS
The importance of hybrid atomic orbitals, in both general and organic chemistry, is reviewed. Every contemporary textbook of organic chemistry introduces the directed-valence (e.g. sp3, sp2, sp) model, but the suitability of these hybrid orbitals for use in the teaching of molecular structure has been increasingly questioned. Based on a critical survey of th
Quím. Nova. Publicado em: 26/08/2019
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11. MOLECULE DESIGN AND PROPERTIES OF CYCLIC ENERGETIC MATERIALS BASED ON NITROGUANIDINE AND 1,1-DIAMINO-2,2-DINITROETHENE
A series of cyclic energetic derivatives based on nitroguanidine and 1,1-diamino-2,2-dinitroethene were theoretically designed. The spatial structures, infrared spectrometry, heats of formation, electronic structures, detonation properties, and thermal stabilities of these designed compounds were fully investigated by density functional theory. It is found t
Quím. Nova. Publicado em: 2019-02
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12. TOPOLOGIA DOS ORBITAIS MOLECULARES DE POLIENOS PARA DEDUZIR ENERGIAS RELATIVAS E AVALIAR AROMATICIDADE
A didactic alternative approach is proposed for deducing the molecular orbital topology of acyclic and cyclic polyenes and then evaluating their bonding, antibonding, and nonbonding character. The relative energies of molecular orbitals of neutral molecules and ions were described, in addition to the orbital degeneracy to cyclic conjugated polyenes, and the
Quím. Nova. Publicado em: 2018-07