Two-Dimensional Infrared Spectroscopy Resolves the Vibrational Landscape in Donor-Bridge-Acceptor Complexes with Site-Specific Isotopic Labeling.

ABSTRACT: Donor-bridge-acceptor complexes (D-B-A) are important model systems for understanding of light-induced processes. Here, we apply two-color two-dimensional infrared (2D-IR) spectroscopy to D-B-A complexes with a trans-Pt(II) acetylide bridge (D-C≡C-Pt-C≡C-A) to uncover the mechanism of vibrational energy redistribution (IVR). Site-selective ¹³C isotopic labeling of the bridge is used to decouple the acetylide modes positioned on either side of the Pt-center. Decoupling of the D-acetylide- from the A-acetylide- enables site-specific investigation of vibrational energy transfer (VET) rates, dynamic anharmonicities, and spectral diffusion. Surprisingly, the asymmetrically labeled D-B-A still undergoes intramolecular IVR between acetylide groups even though they are decoupled

SUBMITTER: Shipp JD 

PROVIDER: S-EPMC11613348 | biostudies-literature | 2024 Nov

REPOSITORIES: biostudies-literature