Near-Infrared Light Emitting Chromium(III) Complexes - Design and Advanced Applications 2.0

近红外发光铬 (III) 配合物 - 设计和高级应用 2.0

• 批准号: 326469115
• 负责人: Professorin Dr. Katja Heinze
• 金额: --
• 依托单位: Department Chemie
• 依托单位国家: 德国
• 项目类别: Research Grants
• 资助国家: 德国
• 项目状态: 未结题
• 来源: https://gepris.dfg.de/gepris/projekt/326469115?language=en
• 关键词: Near; Infrared; Light; Emitting; Chromium

Based on the knowledge gained in NILE-CHROME and complementary expertise of the applicants in ligand design, coordination chemistry, computational chemistry, photochemistry, quantitative optical spectroscopy, nanotechnology, and design of sensor materials, the ground-breaking objectives of this joint project are to rationally design and establish novel complexes based on earth-abundant chromium(III) – the molecular rubies – in novel applications, unavailable for 3d metal complexes or partially even 4d/5d metal complexes so far. This will involve tuning absorption properties, emission energies, (radiative) lifetimes, and O2 sensitivity to enable applications of molecular rubies beyond those reported so far exploiting theory-guided, rationally designed ligands for homo- and heteroleptic chromium(III) complexes. This will include ligands with six-membered chelate rings for a large ligand field splitting, electron dona¬ting/accepting ligands to target emission energies from orange/red to the NIR, ligands to enhance ligand field absorption (tackling the molar absorption coefficient in the visible) and spin-flip emission (tackling the radiative rate) as well as ligands with a negative charge to partially compensate the chromium(III) ion’s high positive charge. Also, tuning of the phosphorescence lifetime and O2 sensitivity by counter anion association will be explored. The application potential of the novel chromium(III) complexes will be shown for photocatalysis, upconversion (UC), circularly polarized luminescence (CPL), lifetime multiplexing, and singlet oxygen generation.The following objectives will be jointly explored:a) Novel ligand designs and novel synthesis procedures for homo- and heteroleptic chromium(III) complexes.b) Excited state landscape design by quantum chemical calculations with multireference methods (CASSCF-NEVPT2) to predict emission energy shifts of chromium(III) spin-flip emitters and obtain information on intersystem crossing (ISC) rates via density of excited states and spin-orbit couplings. ISC rates will be determined experimentally by fs transient absorption spectroscopy and fs transient X-ray emission spectroscopy. c) Excited state energy and electron transfer catalysis of chromium(III) sensitizers with suitable ground and excited state redox potentials like sensitized [2+2], [3+2] and [4+2] cycloadditions.d) CPL properties of chiral chromium(III) complexes for use in a CPL laser e) Use of chromium(III) complexes with suitable doublet excited state 2E/2T1 energies as donors for sensitized triplet-triplet annihilation upconversion (sTTA-UC) with organic dyes. f) Explore whether chromium(III) complexes in sTTA-UC systems can be sensitized with semiconductor quantum dots. g) Assess molecular rubies as labels for lifetime multiplexing. h) Use differently charged chromium(III) complexes as singlet oxygen photosensitizer in cellular studies and for inducing DNA double strand breaks.

基于在 NILE-CHROME 中获得的知识以及申请人在配体设计、配位化学、计算化学、光化学、定量光谱学、纳米技术和传感器材料设计方面的互补专业知识，该联合项目的突破性目标是在新颖的应用中合理设计和建立基于地球丰富的铬（III）（分子红宝石）的新型络合物， 到目前为止，无法用于 3d 金属配合物或部分甚至 4d/5d 金属配合物。这将涉及调整吸收特性、发射能量、（辐射）寿命和 O2 敏感性，以使分子红宝石的应用超出迄今为止报道的利用理论指导、合理设计的均配和杂配铬 (III) 配合物的配体。这将包括用于大配体场分裂的六元螯合环的配体、用于目标发射能量从橙色/红色到近红外的电子给予/接受配体、用于增强配体场吸收（解决可见光中的摩尔吸收系数）和自旋翻转发射（解决辐射率）的配体以及带有负电荷的配体以部分补偿 铬(III)离子的高正电荷。此外，还将探索通过抗衡阴离子缔合调节磷光寿命和 O2 敏感性。新型铬(III)配合物将在光催化、上转换(UC)、圆偏振发光(CPL)、寿命多重和单线态氧生成方面展现出应用潜力。将共同探索以下目标：a)均配和杂配铬(III)配合物的新颖配体设计和新颖合成程序。b)量子激发态景观设计 使用多参考方法（CASSCF-NEVPT2）进行化学计算，以预测铬（III）自旋翻转发射器的发射能量变化，并通过激发态密度和自旋轨道耦合获得系间穿越（ISC）速率的信息。 ISC 速率将通过 fs 瞬态吸收光谱和 fs 瞬态 X 射线发射光谱来实验确定。 c) 具有合适基态和激发态氧化还原电势（如敏化 [2+2]、[3+2] 和 [4+2] 环加成）的铬（III）敏化剂的激发态能量和电子转移催化作用。 d） 用于 CPL 激光器的手性铬（III）配合物的 CPL 特性 e） 使用具有合适双激发态 2E/2T1 能量的铬（III）配合物 作为有机染料敏化三重态-三重态湮灭上转换（sTTA-UC）的供体。 f) 探索 sTTA-UC 系统中的铬（III）配合物是否可以用半导体量子点敏化。 g) 评估分子红宝石作为终生多重分析的标签。 h) 在细胞研究中使用不同电荷的铬 (III) 络合物作为单线态氧光敏剂并诱导 DNA 双链断裂。