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Espectroscopia de imágenes del mapa de velocidad del estado dipolar de CH2 - CN: implicaciones para las bandas

Benjamin A Laws^1,2, Zachariah D Levey¹, Timothy W Schmidt¹

¹School of Chemistry, University of New South Wales, Sydney, NSW 2052, Australia.

Journal of the American Chemical Society

|November 2, 2021

Resumen

Este estudio investiga el anión CH2CN-

Área de la Ciencia:

Química Física
Física y Química
Espectroscopia

Sus antecedentes:

Los sistemas aniónicos débiles ofrecen nuevas vías para la espectroscopia de iones negativos.
El estado dipolado del anión CH2CN es un área clave para la investigación.

Objetivo del estudio:

Para llevar a cabo un estudio multifacético del estado de CH2CN enlazado al dipolo.
Desarrollar un modelo completo de la química de los dipolos.
Para explorar las posibles implicaciones astronómicas del anión CH2CN-.

Principales métodos:

Espectroscopia de fotoelectrones de alta resolución utilizando 130 longitudes de onda.
Imágenes del mapa de velocidad en el umbral.
Escaneo láser para experimentos de desprendimiento.

Principales resultados:

Caracterización detallada de las resonancias de separación automática por vibración y rotación.
Determinación precisa de la afinidad de los electrones (EA = 12468,9(1) cm-1).
Medición precisa de la energía de enlace dipolo (DBE = 40.2(3) cm-1) y la división por inversión de aniones (ω5 = 115.9(2) cm-1).

Conclusiones:

Se estableció un modelo completo de química dipolar para CH2CN-.
La transición de dipolo del anión CH2CN muestra acuerdo con la banda interestelar difusa λ8040, lo que sugiere una posible relevancia astronómica.

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