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oai:figshare.com:article/34040595 2026-10-01T07:04:55Z category_1 category_4 category_915 category_14 category_19 category_272 category_873 category_734 portal_63 item_type_6 month_year_10_2026

Additive-Induced Supramolecular and Structural Isomerism in Zn(II) MOFs: Tuning Emission from Intraligand Local Excitation to Intermolecular Charge Transfer through π–Stacking Control Jian-Di Lin (2179012) Sheng Hu (291314) Hao-Hui Xie (22537468) Qiao-Hong Li (9230902) Zu-Jin Lin (1803883) Fa-Kun Zheng (1918129) Biophysics Biochemistry Physical Sciences not elsewhere classified Molecular Biology Pharmacology Environmental Sciences not elsewhere classified Chemical Sciences not elsewhere classified Biological Sciences not elsewhere classified ligand charge transfer involve intermolecular ligand intraligand local excitation intermolecular charge transfer favors charge transfer despite common ligand controlled noncovalent interactions free ligand ). 2 </ sub based mof family 2 </ b hbtzip )< sub 1 </ b 3 </ b )< sub llct ). versatile strategy tunable materials supramolecular isomers structural isomerism structural isomer space coupling longer separation le ), isophthalic acid induced supramolecular identical one hydrothermally synthesized hirshfeld analysis directed assembly different hydrogen aminoguanidine hydrochloride also establishes allowing le >< b 873 å 657 å (< b Additive-directed assembly is a powerful yet underexplored route to supramolecular isomers with tunable metal–organic framework (MOF) photophysics. Three Zn(II) MOFs, [Zn(Hbtzip)₂(H₂O)₂]·4H₂O (<b>1</b>), [Zn(Hbtzip)₂(H₂O)₂] (<b>2</b>), and [Zn(btzip)] (<b>3</b>), were hydrothermally synthesized from 4,6-bis(triazol-1-yl)isophthalic acid (H₂btzip) using 4,5-dicyanoimidazole, aminoguanidine hydrochloride, and acrylamide as respective additive. <b>1</b> and <b>2</b> are three-dimensional (3D) supramolecular isomers with identical one-dimensional (1D) chains but different hydrogen-bonds and π–π distances; <b>3</b> is a structural isomer with a 3D <i><b>crb</b></i> framework. Despite common ligand-centered emission, they emit at 535 nm (<b>1</b>; 31 nm red shift), 426 nm (<b>2</b>; 78 nm blue shift), and 499 nm (<b>3</b>; nearly identical to free ligand). Through Hirshfeld analysis, time-dependent density functional theory (TDDFT), natural transition orbitals, and electron–hole distributions, we show that <b>1</b> emits via intraligand local excitation (LE), while <b>2</b> and <b>3</b> involve intermolecular ligand-to-ligand charge transfer (LLCT). The shorter π–π distance in <b>2</b> (3.657 Å) enhances through-space coupling and favors charge transfer; the longer separation in <b>1</b> (3.873 Å) weakens it, allowing LE to dominate. This work not only enriches the H₂btzip-based MOF family but also establishes a clear structure–property framework linking supramolecular packing to luminescence, offering a versatile strategy for emission-tunable materials through controlled noncovalent interactions. 2026-10-01T00:00:00Z Text Journal contribution 10.1021/acs.inorgchem.6c04585.s001 https://figshare.com/articles/journal_contribution/Additive-Induced_Supramolecular_and_Structural_Isomerism_in_Zn_II_MOFs_Tuning_Emission_from_Intraligand_Local_Excitation_to_Intermolecular_Charge_Transfer_through_Stacking_Control/34040595 CC BY-NC 4.0