Multicolor-tunable room-temperature afterglow and circularly polarized luminescence in chirality-induced coordination assemblies

Dynamic long-lived multicolor room temperature afterglow and circularly polarized luminescence (CPL) are promising for optoelectronic applications, but integration of these functions into a single-phase chiroptical material is still a difficult and meaningful challenge. Here, a nitrogen-doped benzimidazole molecule 1H-1,2,3-triazolopyridine (Trzpy) showing pure organic room-temperature phosphorescence (RTP) acted as a linker, and then, we propose a chirality-induced coordination assembly strategy to prepare homochiral crystal materials. Two homochiral coordination polymers DCF-10 and LCF-10 not only exhibit multicolor-tunable RTP, the color changed from green to orange under various excitation wavelengths, but also show remarkable excitation-dependent circularly polarized luminescence (CPL), and the dissymmetry factors of CPL in DCF-10 and LCF-10 are 1.8 × 10−3 and 2.4 × 10−3, respectively. Experimental and theoretical studies demonstrated that molecular atmospheres with different aggregation degrees give rise to multiple emission centers for the generation of multicolor-tunable emission. The multicolor-tunable photophysical properties endowed LCF-10 with a huge advantage for multi-level anti-counterfeiting. This work opens up new perspectives for the development and application of color-tunable RTP and CPL.


S1. Methods and Materials
Powder X-ray diffraction (PXRD) patterns were collected on a Bruker D8 ADVANCE diffractometer with Cu Kα (λ = 1.5418 Å) radiation. Measurements were operated power was 40 KV, 30 mA, and a 2θ range of 5−50° at room temperature with a counting time of 0.2 s/ step. Singlecrystal X-ray diffraction data were obtained from Bruker SMART APEX CCD diffractometer equipped with Mo-Kα radiation (λ = 0.71073 Å) at room temperature. The crystal structures were solved by OLEX2. Thermogravimetric analysis (TGA) was performed on a PerkinElmer TG-7 analyzer heated from 30 to 800 °C at the atmosphere with a ramp rate of 5 °C/min. Ultravioletvisible (UV-vis) absorption spectra were collected on a PerkinElmer Lambda spectrophotometer.
The fluorescence and phosphorescence spectra were conducted on Edinburgh FLS1000 with xenon arc lamp and nanosecond flash-lamp. The intrinsic circularly polarized luminescence (CPL) spectra were measured at the scanning speed rate of 100 nm/min on JASCO CPL-300 spectrometer. The circular dichroism (CD) spectra were measured from 200-800 nm range using JASCO J-810 circular dichroism spectrometer.
All reagents and solvents were purchased commercially. Ethyl alcohol (EtOH) and N, N- In fact, we are hungry for a series of chiral coordination polymers to be synthesized via the induction of amino acids, unfortunately, only alanine acids were introduced into chiral coordination polymers. We will continue to prepare chiral frameworks with the incorporation of other amino acids.

S3. The method of recrystallization of Trzpy
1H-1,2,3-Triazolo[4,5-b]pyridine 30 mg was dissolved in 15 ml deionized water in a glass vial, heated at 100 ℃ for 2 hours. Then the vial was kept in the dark at room temperature for slow evaporation of solvent. Well-formed crystals suitable for single crystal X-ray diffraction measurement appeared within approximately four days. The product was isolated prior to total evaporation of the solvent to guarantee the crystal purity.

S4. X-ray Collection and Structure Determination
The diffraction data were measured at 293(2) K under nitrogen flowing with Rigaku supernova CCD system equipped withconfocal monochromated Mo-Kα radiation (λ = 0.71073 Å). All structures were solved by a direct method and refined by using Olex2.0, [1] through the assistance of SHELXTL program. [2] The hydrogen atoms were processed in calculated model directly on the organic ligands and the coordinated solvent molecules. The hydrogen atoms, which was distributed on the coordinated water molecules, were not added due to the lack of hydrogen bond acceptors.
The free solvent molecules and other unambiguously residues were all removed through a SQUEEZE operation by PLATON. [3] Crystallographic data for DCF-10 and LCF-10 are listed in Table S1 and S2.

S5. Computational details
The computational models were built from the crystal structure. The ground state (S 0 ) and excited state geometries of Trzpy are fully optimized by density functional theory (DFT) method and time-S5 dependent density functional theory (TD-DFT) method, respectively. All these calculations are performed by Gaussian 16 package with B3LYP functional and 6-31G(d) basis set. [4] Results and Discussion S6. The UV of Trzpy and PXRD and TGA curves of DCF-10 and LCF-10