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Title: Ultrafast Study of Excited State Dynamics of Amino Metal Halide Molecular Clusters
The excited state dynamics of ligand-passivated PbBr2 molecular clusters (MCs) in solution have been investigated for the first time using femtosecond transient absorption spectroscopy. The results uncover a transient bleach (TB) feature peaked around 404 nm, matching the ground state electronic absorption band peaked at 404 nm. The TB recovery signal can be fitted with a triple exponential with fast (10 ps), medium (350 ps), and long (1.8 ns) time constants. The medium and long time constants are very similar to those observed in the timeresolved photoluminescence (TRPL) decay monitored at 412 nm. The TB fast component is attributed to vibrational relaxation in the excited electronic state while the medium component with dominant amplitude is attributed to recombination between the relaxed electron and hole. The small amplitude slow component is assigned to electrons in a relatively long-lived excited electronic state, e.g., triplet state, or shallow trap state due to defects. This study provides new insights into the excited state dynamics of metal halide MCs.  more » « less
Award ID(s):
2203633
PAR ID:
10537513
Author(s) / Creator(s):
; ;
Publisher / Repository:
ACS
Date Published:
Journal Name:
The Journal of Physical Chemistry Letters
Volume:
14
Issue:
36
ISSN:
1948-7185
Page Range / eLocation ID:
8095 to 8099
Subject(s) / Keyword(s):
amino metal halide molecular clusters ultrafast dynamics
Format(s):
Medium: X
Sponsoring Org:
National Science Foundation
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