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X-ray photoelectron spectroscopy was used to analyze an authentic sample of (η4-cyclooctatetraene)Ru(CO)3 held at 173 K to prevent sublimation of the compound during measurement. This precursor has previously shown utility for photoassisted chemical vapor deposition of Ru species onto alkanethiolate self-assembled monolayers. Herein, we report that the Ru signals for the Ru(0) complex are at a higher binding energy than those of pure Ru metal. 

The electron-induced decomposition of Fe(CO)₄MA (MA = methyl acrylate), which is a potential new precursor for focused electron beam-induced deposition (FEBID), was investigated by surface science experiments under UHV conditions. Auger electron spectroscopy was used to monitor deposit formation. The comparison between Fe(CO)₄MA and Fe(CO)₅revealed the effect of the modified ligand architecture on the deposit formation in electron irradiation experiments that mimic FEBID and cryo-FEBID processes. Electron-stimulated desorption and post-irradiation thermal desorption spectrometry were used to obtain insight into the fate of the ligands upon electron irradiation. As a key finding, the deposits obtained from Fe(CO)₄MA and Fe(CO)₅were surprisingly similar, and the relative amount of carbon in deposits prepared from Fe(CO)₄MA was considerably less than the amount of carbon in the MA ligand. This demonstrates that electron irradiation efficiently cleaves the neutral MA ligand from the precursor. In addition to deposit formation by electron irradiation, the thermal decomposition of Fe(CO)₄MA and Fe(CO)₅on an Fe seed layer prepared by EBID was compared. While Fe(CO)₅sustains autocatalytic growth of the deposit, the MA ligand hinders the thermal decomposition in the case of Fe(CO)₄MA. The heteroleptic precursor Fe(CO)₄MA, thus, offers the possibility to suppress contributions of thermal reactions, which can compromise control over the deposit shape and size in FEBID processes. 

We developed All-ABOARD (Alliance Building Offshore to Achieve Resilience and Diversity) to meet the ever-increasing needs of cultivating a diverse geoscience workforce. All-ABOARD incorporates the Be the Messenger theoretical framework in all programmatic aspects to encourage participants to think about their own identities, positionalities, and privileges. Drawing from US-based institutions, we recruited four teams of four to five members who spanned a spectrum of positionality and career stages. To evaluate the efficacy of the program, we collected both quantitative and qualitative data at different intervals to measure changes in participants’ understanding and perception of identity, culture, respect, and diversity. The year-long core programming included regular webinars via Zoom and an in-person retreat. We found that immersive experiences and intergenerational teams led to the cultivation of a strong identity as a DEI-champion, enhanced group cohesion, and promoted feelings of resilience among participants. Our participants reported they felt most accountable to themselves and their teams, and that learning was accelerated by bringing together teams from multiple institutions to collaborate across intergenerational boundaries. Our program provides a model for training DEI-champions in geoscience who can advance strategic objectives in their home environments and demonstrates how frameworks from the social sciences can be effectively leveraged to transform geoscience. 

We probe the separation of ligands from iron tetracarbonyl methyl acrylate (Fe(CO)₄(C₄H₆O₂) or Fe(CO)₄MA) induced by the interaction with free electrons. The motivation comes from the possible use of this molecule as a nanofabrication precursor and from the corresponding need to understand its elementary reactions fundamental to the electron-induced deposition. We utilize two complementary electron collision setups and support the interpretation of data by quantum chemical calculations. This way, both the dissociative ionization and dissociative electron attachment fragmentation channels are characterized. Considerable differences in the degree of precursor fragmentation in these two channels are observed. Interesting differences also appear when this precursor is compared to structurally similar iron pentacarbonyl. The present findings shed light on the recent electron-induced chemistry of Fe(CO)₄MA on a surface under ultrahigh vacuum. 

Ion beam-induced deposition (IBID) using Pt(CO)₂Cl₂and Pt(CO)₂Br₂as precursors has been studied with ultrahigh-vacuum (UHV) surface science techniques to provide insights into the elementary reaction steps involved in deposition, complemented by analysis of deposits formed under steady-state conditions. X-ray photoelectron spectroscopy (XPS) and mass spectrometry data from monolayer thick films of Pt(CO)₂Cl₂and Pt(CO)₂Br₂exposed to 3 keV Ar⁺, He⁺, and H₂⁺ions indicate that deposition is initiated by the desorption of both CO ligands, a process ascribed to momentum transfer from the incident ion to adsorbed precursor molecules. This precursor decomposition step is accompanied by a decrease in the oxidation state of the Pt(II) atoms and, in IBID, represents the elementary reaction step that converts the molecular precursor into an involatile PtX₂species. Upon further ion irradiation these PtCl₂or PtBr₂species experience ion-induced sputtering. The difference between halogen and Pt sputter rates leads to a critical ion dose at which only Pt remains in the film. A comparison of the different ion/precursor combinations studied revealed that this sequence of elementary reaction steps is invariant, although the rates of CO desorption and subsequent physical sputtering were greatest for the heaviest (Ar⁺) ions. The ability of IBID to produce pure Pt films was confirmed by AES and XPS analysis of thin film deposits created by Ar⁺/Pt(CO)₂Cl₂, demonstrating the ability of data acquired from fundamental UHV surface science studies to provide insights that can be used to better understand the interactions between ions and precursors during IBID from inorganic precursors.