Exploring Directional LLʹCT in (donor)M(acceptor) Complexes
- Author(s): Kramer, Wesley William
- Advisor(s): Heyduk, Alan F
- et al.
The overarching theme of the work presented in this dissertation is the to develope a better understanding of the factors which govern the properties of donor-acceptor (D-A) LL'CT transition metal complexes.
Chapter 2 describes a series of (catcholate)Ni(diimine) D-A LL'CT complexes. The spectroscopic and electrochemical properties can be tuned independently through variations in donor or acceptor ligand electronics.
Chapter 3 describes the Group 10 series of (cat-tBu2)M(bdi) complexes (M = Ni(II), Pd(II), Pt(II); cat-tBu2 = 3,5 di-tert-butylcatecholate; bdi = N,N'- bis(2,4,6-trimethylphenyl)-butane-2,3-diimine). A combination of experimental and computational analyses revealed that the influence of the metal atom in these complexes is limited to the ability of metal ions to participate in pi interactions with the bdi ligand.
Chapter 4 describes the synthesis and characterization of (bdt)M(bdi) and (bds)Pt(bdi), (M = Ni(II), Pd(II), Pt(II); bdt = 1,2-benzenedithiolate, bds = 1,2-benzenediselinolate). In this chapter experimental results are supplemented by computational analysis of the Group 10 series of both donor-acceptor ligand combinations. The results of these investigations indicate that substitution of oxygen for sulfur as the donor ligand heteroatom lowers the donor-localized molecular orbitals and dramatically decreases the variations observed between complexes of different metal ions. Substitution of sulfur for selenium however cause almost no change spectroscopic and electrochemical behavior of the (bds)M(bdi) complexes from the analogous (bdt)M(bdi) complexes.
Chapter 5 provides a thorough computational analysis in to the LL'CT behavior of a series of (donor)Rh(phdi)X2 complexes. These complexes are a rare example of directional LL'CT in an octahedral complex. It was found that alterations of the donor ligand produced predictable changes in the energy of the donor-localized HOMO of these complexes that mirror similar behavior displayed in more traditional square-planar (donor)M(acceptor) LL'CT complexes.