Chemistry Commons^™

Synthesis, Characterization, And Spectroscopy Of Donor-Acceptor Charge Transfer Complexes, Dominic K. Kersi

Chemistry and Chemical Biology ETDs

A series of square-planar metal (diimine)(dichalcogenolene) chromophoric complexes have been synthesized, characterized and studied spectroscopically. Studies conducted on diimineplatinum(II) dichalcogenolene complexes (LPtL’) using time resolved spectroscopic techniques such as transient absorption and emission, reveal a charge-separated excited state of the type dichalcogenolene → diimine charge-transfer (LL’CT) [(dichalcogenolene^•+)Pt(diimine^•-) with an open shell donor-acceptor biradical character. Long-live excited state lifetimes were observed for these complexes upon visible photoexcitation of the LL’CT or MMLL’CT band. A direct linear relationship is observed to exist between photoluminescence rates, calculated SOC matrix elements, and ¹³C-NMR chemical shifts.

A series of …

Comprehensive Silica Removal With Ferric Compounds For Industrial Wastewater Reuse, Ehren D. Baca

Civil Engineering ETDs

Cooling towers, integrated circuit (IC) manufacture and reverse osmosis (RO) generate copious amounts of wastewater high in colloidal and reactive silica inhibiting on-site or synergistic reuse. Silica present in cooling water can reach solubility limits via evaporation and form impervious scale on heat transfer surfaces that decreases efficiency. When water is treated by RO operating at high rejection, silica forms difficult-to-remove scale on the membrane feed side in the form of glassy patches and communities of aggregate particles, inhibiting aspirations for zero liquid discharge. Current methods for silica scale mitigation include abundant dosing with chemical antiscalents or complex operating schemes. …