TY - JOUR

T1 - The effect of halides and coordination mode of 4-amino-2,1,3-benzothiadiazole on the luminescence properties of its Zn complexes

AU - Pylova, Ekaterina K.

AU - Khisamov, Radmir M.

AU - Bashirov, Denis A.

AU - Sukhikh, Taisiya S.

AU - Konchenko, Sergey N.

N1 - Funding Information: The research was supported by the Ministry of Science and Higher Education of the Russian Federation (No. 121031700313-8 and No. 121031700321-3). We are grateful to the Siberian Supercomputer Centre of the Institute of Computational Mathematics and Mathematical Geophysics for computational capability and thank the technical staff of the Institute for their assistance. Publisher Copyright: © 2022 The Royal Society of Chemistry.

PY - 2022/10/20

Y1 - 2022/10/20

N2 - We report a systematic study of the structure-luminescence relationship of novel coordination compounds [ZnL2Br2] (1), [ZnLBr2]n (2), [ZnL2I2] (3) and [ZnLI2]n (4) with 4-amino-2,1,3-benzothiadiazole (L). Variation of the halide and reaction conditions resulted in the formation of four structural types that differ from each other by the coordination mode of L and spatial geometry of the complexes. Drastic differences in the photophysical properties of the compounds were considered in terms of the electronic and stereochemical effects of the halide co-ligands, as well as in terms of the coordination mode of L. The results are discussed by means of TD-DFT quantum chemical calculations in comparison with the previously reported chloride, [ZnL2Cl2]. To interpret electronic transitions in coordination polymer 4, we performed calculations of finite-fragment cropped models, which are quite a common approximation used for coordination polymers. However, the finite models of different length gave questionable results. To overcome this problem, TD-DFPT calculations using a periodic model were performed, which gave a more correct interpretation of the electronic transitions. Compound 1 features a dual-band emission spanning the entire visible region. The long wavelength band is attributed to free L as a dopant in crystals of 1 implying the energy transfer from the excited state of the complex to L. Iterative treatment of the powder with hexane can control the doping concentration of L and, as a consequence, the emission colour. The prepared film of 1 in a polystyrene matrix shows a similar emission, but with increased intensity of the long wavelength band, which results in a warmer luminescent colour.

AB - We report a systematic study of the structure-luminescence relationship of novel coordination compounds [ZnL2Br2] (1), [ZnLBr2]n (2), [ZnL2I2] (3) and [ZnLI2]n (4) with 4-amino-2,1,3-benzothiadiazole (L). Variation of the halide and reaction conditions resulted in the formation of four structural types that differ from each other by the coordination mode of L and spatial geometry of the complexes. Drastic differences in the photophysical properties of the compounds were considered in terms of the electronic and stereochemical effects of the halide co-ligands, as well as in terms of the coordination mode of L. The results are discussed by means of TD-DFT quantum chemical calculations in comparison with the previously reported chloride, [ZnL2Cl2]. To interpret electronic transitions in coordination polymer 4, we performed calculations of finite-fragment cropped models, which are quite a common approximation used for coordination polymers. However, the finite models of different length gave questionable results. To overcome this problem, TD-DFPT calculations using a periodic model were performed, which gave a more correct interpretation of the electronic transitions. Compound 1 features a dual-band emission spanning the entire visible region. The long wavelength band is attributed to free L as a dopant in crystals of 1 implying the energy transfer from the excited state of the complex to L. Iterative treatment of the powder with hexane can control the doping concentration of L and, as a consequence, the emission colour. The prepared film of 1 in a polystyrene matrix shows a similar emission, but with increased intensity of the long wavelength band, which results in a warmer luminescent colour.

UR - http://www.scopus.com/inward/record.url?scp=85142379587&partnerID=8YFLogxK

U2 - 10.1039/d2ce01215d

DO - 10.1039/d2ce01215d

M3 - Article

AN - SCOPUS:85142379587

VL - 24

SP - 8256

EP - 8265

JO - CrystEngComm

JF - CrystEngComm

SN - 1466-8033

IS - 47

ER -