Unusual electronic absorption changes in the 800–2200 nm region by intramolecular dimer radical cations from photoirradiated meso-2,4-bis[4-(4′-nitrostyryl)pyridinium]pentane ditetraphenylborates during storage in the dark

Abstract

Electronic absorption spectra were remarkably changed in the broad near-infrared region for photoirradiated meso-2,4-bis[4-(4′-nitrostyryl)pyridinium]pentane ditetraphenylborates during storage in the dark, which was attributed to conformational changes of the intramolecular dimer radical cations between sandwich and partially overlapped types.