Dataset Information

Borylation in the Second Coordination Sphere of Fe^II Cyanido Complexes and Its Impact on Their Electronic Structures and Excited-State Dynamics.

ABSTRACT: Second coordination sphere interactions of cyanido complexes with hydrogen-bonding solvents and Lewis acids are known to influence their electronic structures, whereby the non-labile attachment of B(C₆F₅)₃ resulted in several particularly interesting new compounds lately. Here, we investigate the effects of borylation on the properties of two Fe^II cyanido complexes in a systematic manner by comparing five different compounds and using a range of experimental techniques. Electrochemical measurements indicate that borylation entails a stabilization of the Fe^II-based t_2g-like orbitals by up to 1.65 eV, and this finding was confirmed by Mössbauer spectroscopy. This change in the electronic structure has a profound impact on the UV-vis absorption properties of the borylated complexes compared to the non-borylated ones, shifting their metal-to-ligand charge transfer (MLCT) absorption bands over a wide range. Ultrafast UV-vis transient absorption spectroscopy provides insight into how borylation affects the excited-state dynamics. The lowest metal-centered (MC) excited states become shorter-lived in the borylated complexes compared to their cyanido analogues by a factor of ∼10, possibly due to changes in outer-sphere reorganization energies associated with their decay to the electronic ground state as a result of B(C₆F₅)₃ attachment at the cyanido N lone pair.

SUBMITTER: Schmid L

PROVIDER: S-EPMC9554916 | biostudies-literature | 2022 Oct

REPOSITORIES: biostudies-literature

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Borylation in the Second Coordination Sphere of FeII Cyanido Complexes and Its Impact on Their Electronic Structures and Excited-State Dynamics.

Schmid Lucius L Chábera Pavel P Rüter Isabelle I Prescimone Alessandro A Meyer Franc F Yartsev Arkady A Persson Petter P Wenger Oliver S OS

Inorganic chemistry 20220927 40

Second coordination sphere interactions of cyanido complexes with hydrogen-bonding solvents and Lewis acids are known to influence their electronic structures, whereby the non-labile attachment of B(C6F5)3 resulted in several particularly interesting new compounds lately. Here, we investigate the effects of borylation on the properties of two FeII cyanido complexes in a systematic manner by comparing five different compounds and using a range of experi ...[more]

PMID: 36167335

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Dataset Information

Borylation in the Second Coordination Sphere of Fe^II Cyanido Complexes and Its Impact on Their Electronic Structures and Excited-State Dynamics.

Publications

Borylation in the Second Coordination Sphere of Fe<sup>II</sup> Cyanido Complexes and Its Impact on Their Electronic Structures and Excited-State Dynamics.

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