Abstract
We describe a novel manifestation of rigidochromic behavior in a series of tetranuclear Cu(I)–pyrazolate (Cu4pz4) macrocycles, with implications for solid-state luminescence at deep-blue wavelengths (<460 nm). The Cu4pz4 emissions are remarkably sensitive to structural effects far from the luminescent core: when 3,5-di-tert-butylpyrazoles are used as bridging ligands, adding a C4 substituent can induce a blue shift of more than 100 nm. X-ray crystal and computational analyses reveal that C4 units influence the conformational behavior of adjacent tert-butyl groups, with a subsequent impact on the global conformation of the Cu4pz4 complex. Emissions are mediated primarily through a cluster-centered triplet (3CC) state; compression of the Cu4 cluster into a nearly close-packed geometry prevents the reorganization of its excited-state structure and preserves the 3CC energy at a high level. The remote steric effect may thus offer alternative strategies toward the design of phosphors with rigid excited-state geometries.
Date of this Version
5-20-2022
Recommended Citation
Watanabe, Yuichiro; Washer, Benjamin M.; Zeller, Matthias; Savikhin, Sergei; Slipchenko, Lyudmila V.; and Wei, Alexander, "Copper(I)‒Pyrazolate Complexes as Solid-State Phosphors: Deep-
Blue Emission Through a Remote Steric Effect" (2022). Department of Chemistry Faculty Publications. Paper 21.
https://docs.lib.purdue.edu/chempubs/21
Comments
This is the author-accepted manuscript of Watanabe, Y; Washer, B; Zeller, M; Savikhin, S; Slipchenko, L; and Wei, A. (2022) Copper(I)–Pyrazolate Complexes as Solid-State Phosphors: Deep-Blue Emission through a Remote Steric Effect. Journal of the American Chemical Society, 144, 23, 10186–10192. Copyright American Chemical Society, the version of record is available at DOI: 10.1021/jacs.1c13462.