For instance, as the number of benzene rings fused with the thiophene unit rises (4-7), the rigidity of molecules gradually increases accordingly . Compared to dilute solutions, COTh derivatives exhibit fluorescence enhancement and hypsochromic shift in the aggregated state. Then, two COTh-TMS units were functionalized with nitrogensubstituted heterocycles , namely triazinyl, phenanthrolinyl, and pyridyl, serving as the central unit (8-10). The disparities in luminescence intensity and peak displacement caused by varying structures elucidate the influence of intramolecular S• • • N (molecular rigidity) and intermolecular π-π interactions (crystal packing) on the AIE characteristics.