Mechanochromic luminescence properties of fluoro-substituted pinene-containing cyclometalated platinum(ii) complexes with multiple triplet excited states. Issue 25 (10th June 2021)

• Record Type: Journal Article
• Authors: Yang, Qian-Ying; Zhang, Hua-Hong; Qi, Xiao-Wei; Sun, Shi-Shu; Zhang, Da-Shuai; Han, Li-Zhi; Zhang, Xiao-Peng; Shi, Zai-Feng
• Is Part Of: Dalton transactions. Volume 50:Issue 25(2021)
• Page Start: 8938
• Page End: 8946
• Publication Date: 2021-06-10
• Subjects: Chemistry, Inorganic -- Periodicals; Chemistry, Physical and theoretical -- Periodicals; Chemistry, Inorganic -- Periodicals; 546.05
• DOI: 10.1039/d1dt00848j
• Languages: English
• ISSNs: 1477-9226

Abstract

Abstract : The distinct and reversible mechanochormic luminescence of as-prepared yellow solids of (−)-2 are displayed. The interplay of 3 π, π* monomer and excimer/ 3 MMLCT excited states is supposed to be the key for mechanochromic luminescence. Abstract : The structure–mechanochromism relationship is explored with respect to packing patterns and corresponding intermolecular interactions that are affected by the number and location of –F. The distinct and reversible mechanochormic luminescence (Δ λ em up to ca. 90 nm) of yellow solids (−)-1-Yg, (−)-2-Yg, and (−)-3-Yg was displayed with a simultaneous crystal-to-amorphous transformation. The change of multiple triplet excited states accounted for the mechanochormic luminescence, and a switch from the 3 π, π* monomer to the excimer/ 3 MMLCT occurred in the grinding process. The mechanical force led to perturbation in the molecular packing, and aggregates with effective Pt⋯Pt and π–π interactions were formed in the amorphous phase, leading to the variation of excited states. The mechanochromic luminescence could be reverted by dropping in CH2 Cl2 and could be cycled multiple times without perceivable performance degradation. This work gives a reference for designing mechanochromic luminescent materials toward multicolor and multicomponent responses.