Interrogating ultrafast dynamics of a salicylideneaniline derivative within faujasite zeolites

We report on femtosecond (fs) studies of (E)-2-(2-hydroxybenzyliden) amino-4-nitrophenol (HBA-4NP) in dichloromethane (DCM) and triacetin (TAC) solutions, and within NaX and NaY zeolites. In solution, an ultrafast (≤80 fs) excited-state intramolecular proton-transfer (ESIPT) reaction produces a keto (K) tautomer, which undergoes a rotational process in ∼4 (DCM) and ∼7 ps (TAC) toward the formation of non-emitting structures. Within NaX and NaY, where monomers and aggregates are formed, host-guest and guest-guest interactions play an important role in the ultrafast behaviour of these complexes. These results clearly reflect how nanoconfinement and zeolite composition affect the encapsulated dye photodynamics.This work was supported by the JCCM and MINECO through projects: PEII-2014-003-P, Consolider Ingenio 2010 (CSD2009- 0050, MULTICAT), MAT2014-57646-P and CEI15-08-5‘‘CEI CYTEMA”. N. A. thanks the CYTEMA program for the postdoctoral fellowshipPeer Reviewe