AUTHOR=Yang Qian-Ying , Zhang Hua-Hong , Han Xue-Ling , Weng Shi-Dao , Chen Yuan , Wu Jia-Li , Han Li-Zhi , Zhang Xiao-Peng , Shi Zai-Feng TITLE=Enhanced Circularly Polarized Luminescence Activity in Chiral Platinum(II) Complexes With Bis- or Triphenylphosphine Ligands JOURNAL=Frontiers in Chemistry VOLUME=Volume 8 - 2020 YEAR=2020 URL=https://www.frontiersin.org/journals/chemistry/articles/10.3389/fchem.2020.00303 DOI=10.3389/fchem.2020.00303 ISSN=2296-2646 ABSTRACT=Distinct circularly polarized luminescence (CPL) activity was observed in chiral (C^N^N)Pt(II) ([C^N^N] = 4,5-pinene-6'-phenyl-2,2'-bipyridine) complexes with bis- or tri-phenylphosphine ligands. Compared to pseudo square-planar geometry of chiral (C^N^N)Pt(II) complexes with chloride, phenylacetylene (PPV) and 2,6-dimethylphenyl isocyanide (Dmpi) ligands, the coordination configuration around Pt(II) nucleus of chiral (C^N^N)Pt(II) complexes with bulk phosphine ligands is far more distorted. The geometry is straightforwardly confirmed by X-ray crystallography. The phosphines’ participation enhanced the CPL signal of Pt(II) complexes profoundly, with the dissymmetry factor (glum) up to 10-3. The distorted structures and enhanced chiroptical signals was further confirmed by TD-DFT calculations.