@article{salazar_brewer_mcelwee-white_walker_2022, title={Photoactivated Ru chemical vapor deposition using (η3-allyl)Ru(CO)3X (X = Cl, Br, I): From molecular adsorption to Ru thin film deposition}, volume={40}, url={http://dx.doi.org/10.1116/6.0001490}, DOI={10.1116/6.0001490}, abstractNote={We have investigated photoassisted chemical vapor deposition (PACVD) of Ru on functionalized alkanethiolate self-assembled monolayers (SAMs) using (η3-allyl)Ru(CO)3X (X = Cl, Br, I) precursors. Three SAMs were employed with —CH3, —OH, or —COOH terminal groups. Our data show that (η3-allyl)Ru(CO)3Cl molecularly adsorbs on the functionalized SAMs and no Ru(0) is deposited in either the dark or under UV light. Similarly, (η3-allyl)Ru(CO)3I molecularly adsorbs on all substrates studied. For (η3-allyl)Ru(CO)3Br at longer deposition times under UV light, Ru(0) and RuOx are deposited on —CH3- and —OH-terminated SAMs. In contrast for —COOH-terminated SAMs, little or no Ru is deposited, which is attributed to the formation of Ru-carboxylate complexes that block further deposition. Density Functional Theory calculations show that the different deposition behaviors observed are not due to the primary photoprocess, which is the loss of a carbonyl ligand, but rather can be attributed to the energy required to lose a second carbonyl ligand, a secondary photoprocess. Together, these data suggest that PACVD can be employed for area selective deposition.}, number={2}, journal={Journal of Vacuum Science & Technology A}, publisher={American Vacuum Society}, author={Salazar, Bryan G. and Brewer, Christopher R. and McElwee-White, Lisa and Walker, Amy V.}, year={2022}, month={Jan}, pages={023404} }
 @article{brewer_sheehan_herrera_walker_mcelwee-white_2022, title={Photochemistry of (η4-diene)Ru(CO)3 Complexes as Precursor Candidates for Photoassisted Chemical Vapor Deposition}, volume={41}, url={https://doi.org/10.1021/acs.organomet.1c00715}, DOI={10.1021/acs.organomet.1c00715}, abstractNote={Solution phase photochemical experiments on (η4-diene)Ru(CO)3 complexes (diene = butadiene, isoprene, 1,3-cyclohexadiene, or cyclobutadiene) demonstrated loss of both diene and CO, making them attractive precursors for photoassisted chemical vapor deposition of ruthenium. Pathways including loss of one CO ligand, loss of diene, loss of two CO ligands, and loss of CO plus diene were observed. Quantum yields for loss of a single CO or diene ligand as the primary photoprocess were determined for the (η4-diene)Ru(CO)3 complexes and were found to be dependent on the structure of the diene. Subsequent ligand loss was determined to occur from secondary photolysis. Very little luminescence was observed for the compounds, demonstrating that radiative decay of the excited states was not competitive with photochemical ligand loss. Exhaustive photolysis experiments confirmed that all of the dienes, except for cyclobutadiene, were photolytically labile. In the absence of phosphite, the (η4-diene)Ru(CO)3 complexes showed evidence for formation of colloidal Ru species following irradiation in hydrocarbon solutions.}, number={6}, journal={Organometallics}, publisher={American Chemical Society (ACS)}, author={Brewer, Christopher R. and Sheehan, Nicholas C. and Herrera, Jessica and Walker, Amy V. and McElwee-White, Lisa}, year={2022}, month={Mar}, pages={761–775} }
 @article{stribling_brewer_goldsby_2021, title={Resuscitating the Mercury Beating Heart: An Improvement on the Classic Demo}, volume={98}, url={https://doi.org/10.1021/acs.jchemed.0c00845}, DOI={10.1021/acs.jchemed.0c00845}, abstractNote={The mercury beating heart is a dramatic demonstration of redox chemistry that allows for the direct conversion of chemical energy to mechanical energy without involving a machine to accomplish the ...}, number={2}, journal={Journal of Chemical Education}, publisher={American Chemical Society (ACS)}, author={Stribling, Daniel and Brewer, Christopher R. and Goldsby, Kenneth A.}, year={2021}, month={Feb}, pages={662–664} }
 @article{rohdenburg_boeckers_brewer_mcelwee-white_swiderek_2020, title={Efficient NH3-based process to remove chlorine from electron beam deposited ruthenium produced from (η3-C3H5)Ru(CO)3Cl}, volume={10}, url={https://doi.org/10.1038/s41598-020-67803-y}, DOI={10.1038/s41598-020-67803-y}, abstractNote={Abstract}, number={1}, journal={Scientific Reports}, publisher={Springer Science and Business Media LLC}, author={Rohdenburg, Markus and Boeckers, Hannah and Brewer, Christopher R. and McElwee-White, Lisa and Swiderek, Petra}, year={2020}, month={Dec} }
 @article{liu_brewer_walker_mcelwee-white_2020, title={Photochemistry of 1,5-Cyclooctadiene Platinum Complexes for Photoassisted Chemical Vapor Deposition}, volume={39}, url={https://doi.org/10.1021/acs.organomet.0c00616}, DOI={10.1021/acs.organomet.0c00616}, abstractNote={Quantum yields for disappearance of (COD)PtMe2 (1a) and (COD)PtMeCl (1b) were determined at 334 nm in C6D6 solvent. Chain reactions initiated by formation of a methyl radical were proposed to be th...}, number={24}, journal={Organometallics}, publisher={American Chemical Society (ACS)}, author={Liu, Hanwen and Brewer, Christopher R. and Walker, Amy V. and McElwee-White, Lisa}, year={2020}, month={Dec}, pages={4565–4574} }
 @article{cipriani_thorman_brewer_mcelwee-white_ingólfsson_2019, title={Dissociative ionization of the potential focused electron beam induced deposition precursor π-allyl ruthenium(II) tricarbonyl bromide, a combined theoretical and experimental study}, volume={73}, DOI={10.1140/epjd/e2019-100151-9}, number={10}, journal={The European Physical Journal D}, publisher={Springer Science and Business Media LLC}, author={Cipriani, Maicol and Thorman, Rachel M. and Brewer, Christopher R. and McElwee-White, Lisa and Ingólfsson, Oddur}, year={2019}, month={Oct} }
 @article{jurczyk_brewer_hawkins_polyakov_kapusta_mcelwee-white_utke_2019, title={Focused Electron Beam-Induced Deposition and Post-Growth Purification Using the Heteroleptic Ru Complex (η3-C3H5)Ru(CO)3Br}, volume={11}, url={https://doi.org/10.1021/acsami.9b07634}, DOI={10.1021/acsami.9b07634}, abstractNote={Focused electron beam induced deposition using the heteroleptic complex (η3-C3H5)Ru(CO)3Br as a precursor resulted in deposition of material with Ru content of 23 at%. TEM images indicated a nanogranular structure of pure Ru nanocrystals, embedded into a matrix containing carbon, oxygen and bromine. The deposits were purified by annealing in a reactive 98% N2 / 2% H2 atmosphere at 300 ºC, resulting in reduction of contaminants and an increase of Ru content to 83 at%. Although a significant 79% volume loss was found, the shrinkage was observed mostly for vertical thickness (around 75%). Lateral dimensions decreased but much less significantly (around 9%). Deposition results, in conjunction with previous gas phase and condensed phase surface studies on the electron-induced reactions of (η3-C3H5)Ru(CO)3Br, provide insight into the behavior of allyl, carbonyl and bromide ligands under identical electron beam irradiation.}, number={31}, journal={ACS Applied Materials & Interfaces}, publisher={American Chemical Society (ACS)}, author={Jurczyk, Jakub and Brewer, Christopher R. and Hawkins, Olivia M. and Polyakov, Mikhail N. and Kapusta, Czeslaw and McElwee-White, Lisa and Utke, Ivo}, year={2019}, month={Aug}, pages={28164–28171} }
 @article{brewer_hawkins_sheehan_bullock_kleiman_walker_mcelwee-white_2019, title={Photochemistry of (η3-allyl)Ru(CO)3X Precursors for Photoassisted Chemical Vapor Deposition}, volume={38}, url={https://doi.org/10.1021/acs.organomet.9b00628}, DOI={10.1021/acs.organomet.9b00628}, abstractNote={Quantum yields for loss of a single CO ligand in alkane solutions were determined for the (η3-allyl)Ru(CO)3X complexes, where X = Cl, Br, I. The three complexes had similar quantum yields at λexc =...}, number={21}, journal={Organometallics}, publisher={American Chemical Society (ACS)}, author={Brewer, Christopher R. and Hawkins, Olivia M. and Sheehan, Nicholas C. and Bullock, James D. and Kleiman, Valeria D. and Walker, Amy V. and McElwee-White, Lisa}, year={2019}, month={Nov}, pages={4363–4370} }
 @article{johnson_rodriguez_brewer_brannaka_shi_yang_salazar_mcelwee-white_walker_2017, title={Photochemical CVD of Ru on functionalized self-assembled monolayers from organometallic precursors}, volume={146}, url={https://doi.org/10.1063/1.4971434}, DOI={10.1063/1.4971434}, abstractNote={Chemical vapor deposition (CVD) is an attractive technique for the metallization of organic thin films because it is selective and the thickness of the deposited film can easily be controlled. However, thermal CVD processes often require high temperatures which are generally incompatible with organic films. In this paper, we perform proof-of-concept studies of photochemical CVD to metallize organic thin films. In this method, a precursor undergoes photolytic decomposition to generate thermally labile intermediates prior to adsorption on the sample. Three readily available Ru precursors, CpRu(CO)2Me, (η3-allyl)Ru(CO)3Br, and (COT)Ru(CO)3, were employed to investigate the role of precursor quantum yield, ligand chemistry, and the Ru oxidation state on the deposition. To investigate the role of the substrate chemistry on deposition, carboxylic acid-, hydroxyl-, and methyl-terminated self-assembled monolayers were used. The data indicate that moderate quantum yields for ligand loss (φ ≥ 0.4) are required for ruthenium deposition, and the deposition is wavelength dependent. Second, anionic polyhapto ligands such as cyclopentadienyl and allyl are more difficult to remove than carbonyls, halides, and alkyls. Third, in contrast to the atomic layer deposition, acid-base reactions between the precursor and the substrate are more effective for deposition than nucleophilic reactions. Finally, the data suggest that selective deposition can be achieved on organic thin films by judicious choice of precursor and functional groups present on the substrate. These studies thus provide guidelines for the rational design of new precursors specifically for selective photochemical CVD on organic substrates.}, number={5}, journal={The Journal of Chemical Physics}, publisher={AIP Publishing}, author={Johnson, Kelsea R. and Rodriguez, Paul Arevalo and Brewer, Christopher R. and Brannaka, Joseph A. and Shi, Zhiwei and Yang, Jing and Salazar, Bryan and McElwee-White, Lisa and Walker, Amy V.}, year={2017}, month={Feb}, pages={052816} }
 @article{chem_2016, title={Cu(II)-Catalyzed Oxidative Formation of 5,5′-Bistriazoles}, volume={81}, url={http://pubs.acs.org/doi/abs/10.1021/acs.joc.6b01907}, DOI={10.1021/acs.joc.6b01907}, abstractNote={Copper(II) acetate under aerobic conditions catalyzes the formation of 5,5'-bis(1,2,3-triazole)s (5,5'-bistriazoles) from organic azides and terminal alkynes. This reaction is an oxidative extension of the widely used copper-catalyzed azide-alkyne "click" cycloaddition. The inclusion of potassium carbonate as an additive and methanol or ethanol as the solvent, and in many instances an atmosphere of dioxygen, promote the oxidative reaction to afford 5,5'-bistriazole at the expense of 5-protio-1,2,3-triazole (5-protiotriazole). If needed, tris[(1-benzyl-1H-1,2,3-triazol-4-yl)methyl]amine (TBTA) as a ligand additive further accelerates the formation of 5,5'-bistriazoles. A convenient procedure to prepare TBTA is also reported to facilitate the adoption of this method for preparation of 5,5'-bistriazoles. Aromatic azide-derived 5,5'-bistriazoles possess rigid axially chiral structures with a broad distribution of dihedral angles, which may be explored as chiral ligands in enantioselective catalysis if decorated with proper functional groups.}, number={24}, journal={Journal of Organic Chemistry}, author={Chem, J.Org}, year={2016}, month={Dec}, pages={12091–12105} }