In search of new multifunctional hybrid materials and in order to investigate the influence of chemical modification on the possible synergy between properties, the carboxylate and sulfonate derivatives of photo- and thermochromic N-salicylidene aniline were successfully inserted into Co(II)- and Zn(II)-based layered simple hydroxides, resulting in four novel hybrids: Co-N-Sali-COO, Co-N-Sali-SO3, Zn-N-Sali-COO, and Zn-N-Sali-SO3. All synthesized hybrids adopt a double organic layered configuration, which prevents the cis-trans photoisomerization ability of N-Sali-R molecules in the hybrids. However, the Zn hybrids exhibit fluorescence upon exposure to UV light due to the excited-state intramolecular proton transfer (ESIPT) mechanism. The thermally stimulated keto-enol tautomerization of N-salicylidene aniline in the hybrids was related with the changes in interlamellar spacings observed by temperature-dependent PXRD. This tautomerization process was prominently evident in the Co-N-Sali-SO3 hybrid (about 11% increase in d-spacing upon decreasing the temperature to -180 degrees C). Finally, the Co-N-Sali-R hybrids exhibit the typical magnetic behavior associated with Co(II)-based LSHs (ferrimagnetic ordering at T-N = 6.8 and 7.7 K for Co-N-Sali-COO and Co-N-Sali-SO3, respectively). This work offers insights into isomerization in LSHs and the ESIPT mechanism's potential in new luminescent materials and prospects for designing new multifunctional materials

Inorg. Chem.
High-Harmonic Generation and EUV Science

Kumar, V., Evrard, Q., Leuvrey, C., Lenertz, M., Garcia, Y., Rabu, P., & Rogez, G. (2023). Incorporation of Photo- and Thermoresponsive N-Salicylidene Aniline Derivatives into Cobalt and Zinc Layered Hydroxides. Inorg. Chem., 62(51), 21101–21114. doi:10.1021/acs.inorgchem.3c03013