Video Experimental Relacionado
Updated: Jul 17, 2026
08:07
Ultrahigh Density Array of Vertically Aligned Small-molecular Organic Nanowires on Arbitrary Substrates
Published on: June 18, 2013
Oligoacenos ricos en nitrógeno: candidatos para los semiconductores orgánicos de n canales
1Institut für Organische Chemie, Universität Würzburg, Am Hubland, 97074 Würzburg, Germany. winkler@chemie.uni-wuerzburg.de
Journal of the American Chemical Society
|January 26, 2007
Resumen
La sustitución del carbono-hidrógeno (CH) por nitrógeno en los oligoacenos crea semiconductores de n canales prometedores. Los heptaazapentacenos con arreglos específicos de nitrógeno exhiben altas afinidades electrónicas y bajas energías de reorganización para una transferencia eficiente de electrones.
Área de la Ciencia:
- Química computacional es la química computacional.
- Ciencia de los materiales ciencia de los materiales.
- La electrónica orgánica es la electrónica orgánica.
Sus antecedentes:
- Los oligoacenos son semiconductores orgánicos con aplicaciones potenciales en la electrónica.
- El ajuste de las propiedades electrónicas a través de la sustitución heteroatómica es una estrategia clave para el diseño de materiales.
Objetivo del estudio:
- Investigar el impacto de la sustitución de grupos CH por átomos de nitrógeno en los oligoacenos.
- Identificar nuevos materiales orgánicos semiconductores con afinidad electrónica mejorada y propiedades de transporte de carga.
Principales métodos:
- Estudio computacional utilizando el nivel teórico B3LYP/6-311+G(d,p)//6-31G(d).
- Análisis de las propiedades estructurales, electrónicas y energéticas de los oligoacenos sustituidos por nitrógeno.
Principales resultados:
- El logro de altas afinidades de electrones (>3 eV) requiere una incorporación significativa de nitrógeno (≥7 átomos) en tetracenos o pentacenos.
- Los heptaazapentacenos muestran estructuras autocomplementarias y interacciones intermoleculares favorables.
- Los azacenos cyanosubstituidos exhiben energías de reorganización más bajas (0.130.14 eV) y altas afinidades de electrones (3.3 eV).
Conclusiones:
- Los oligoacenos ricos en nitrógeno, particularmente los heptaazapentacenos, son candidatos prometedores para los semiconductores orgánicos de n canales.
- Las estructuras autocomplementarias y las fuertes interacciones intermoleculares N-C(H) mejoran el transporte de carga y la estabilidad del aire.
- La funcionalización con grupos de ciano optimiza aún más las propiedades electrónicas para aplicaciones de materiales.
Videos de Conceptos Relacionados
01:20Anionic Chain-Growth Polymerization: Overview
The polymerization process that involves carbanion as an intermediate is called anionic polymerization. It is also a type of addition or chain-growth polymerization. Anionic polymerization gets initiated by a strong nucleophile such as an organolithium or a Grignard reagent. The most commonly used initiator for anionic polymerization is butyl lithium. Monomers involved in anionic polymerization must possess a vinyl group bonded to one or two electron-withdrawing groups. For instance,...
01:28Structures of Carboxylic Acid Derivatives
Structure of Carboxylic Acid Derivatives
Carboxylic acid derivatives contain an acyl group attached to a heteroatom such as chlorine, oxygen, or nitrogen. The carbonyl carbon and oxygen are both sp2-hybridized with an unhybridized p orbital.
The three sp2 orbitals of the carbonyl carbon form three σ bonds, one each with the carbonyl oxygen, the α carbon, and the heteroatom, whereas the other two sp2 orbitals of the carbonyl oxygen are occupied by the lone pairs. Further, the unhybridized p...
Carboxylic acid derivatives contain an acyl group attached to a heteroatom such as chlorine, oxygen, or nitrogen. The carbonyl carbon and oxygen are both sp2-hybridized with an unhybridized p orbital.
The three sp2 orbitals of the carbonyl carbon form three σ bonds, one each with the carbonyl oxygen, the α carbon, and the heteroatom, whereas the other two sp2 orbitals of the carbonyl oxygen are occupied by the lone pairs. Further, the unhybridized p...
01:202° Amines to N-Nitrosamines: Reaction with NaNO2
Secondary amines react with nitrous acid to form N-nitrosamines, as depicted in Figure 1. Nitrous acid, a weak and unstable acid, is formed in situ from an aqueous solution of sodium nitrite and strong acids, such as hydrochloric acid or sulfuric acid, in cold conditions. In the presence of an acid, the nitrous acid gets protonated. The subsequent loss of water results in the formation of the electrophile known as nitrosonium ion.
01:261° Amines to Diazonium or Aryldiazonium Salts: Diazotization with NaNO2 Overview
Nitrous acid and nitric acids are two types of acids containing nitrogen, among which nitrous acid is weaker than nitric acid. Nitrous acid with a pKa value of 3.37 ionizes in water to give a nitrite ion and the hydronium ion.
The nitrous acid is unstable. Hence, it is formed in situ from a solution of sodium nitrite and cold aqueous acids such as hydrochloric or sulfuric acid. In an acidic solution, the –OH group of nitrous acid undergoes protonation to give oxonium ion, followed by water loss...
The nitrous acid is unstable. Hence, it is formed in situ from a solution of sodium nitrite and cold aqueous acids such as hydrochloric or sulfuric acid. In an acidic solution, the –OH group of nitrous acid undergoes protonation to give oxonium ion, followed by water loss...
01:371° Amines to Diazonium or Aryldiazonium Salts: Diazotization with NaNO2 Mechanism
Nitrous acid is a relatively weak and unstable acid prepared in situ by the reaction of sodium nitrite and cold, dilute hydrochloric acid. In an acidic solution, the nitrous acid undergoes protonation when it loses water to form a nitrosonium ion—an electrophile. Nitrous acid reacts with primary amines to give diazonium salts. The reaction is called diazotization of primary amines.
01:17Ziegler–Natta Chain-Growth Polymerization: Overview
Ziegler–Natta polymerization is another form of addition or chain‐growth polymerization used for synthesizing linear polymers over branched polymers. The catalyst used for polymerization is the Ziegler–Natta catalyst, named after Karl Ziegler and Giulio Natta, who developed it in 1953. This catalyst is an organometallic complex of titanium tetrachloride and triethyl aluminum, with the active form of the catalyst being an alkyl titanium compound. Using the Ziegler–Natta catalyst, high molecular...