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Title: Vibrational Spectroscopy and Structural Analysis of V+(C2H6)n Clusters (n = 1–4)
The vibrational structure and binding motifs of vanadium cation-ethane clusters, V(+)(C2H6)n, for n = 1 – 4 are probed using infrared photodissociation spectroscopy in the C-H stretching region (2550 – 3100 cm-1). Comparison of spectra to scaled harmonic frequency spectra obtained using density functional theory suggest that ethane exhibits two primary binding motifs when interacting with the vanadium cation, an end-on 𝜂2 configuration and a side-on configuration. The lower-energy side-on configuration predominates in smaller clusters, but the end-on configuration becomes important for larger clusters as it helps to maintain a roughly square planar geometry about the central vanadium. Proximate C-H bonds exhibit elongation and large red-shifts when compared to bare ethane, particularly in the case of the side-on isomer, which are underestimated by scaled harmonic frequency calculations, demonstrating initial effects of C-H bond activation.  more » « less
Award ID(s):
1856490
PAR ID:
10519878
Author(s) / Creator(s):
;
Publisher / Repository:
ACS
Date Published:
Journal Name:
The Journal of Physical Chemistry A
Volume:
127
Issue:
24
ISSN:
1089-5639
Page Range / eLocation ID:
5091 to 5103
Subject(s) / Keyword(s):
non-covalent interactions C-H activation vibrational spectroscopy
Format(s):
Medium: X
Sponsoring Org:
National Science Foundation
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