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Linic, Suljo

Publications and source records attributed to Linic, Suljo.

39 records · Page 3

Epoxidation catalyst and process

Disclosed herein is a catalytic method of converting alkenes to epoxides. This method generally includes reacting alkenes with oxygen in the presence of a specific silver catalyst under conditions suitable to produce a yield of the epoxides. The specific silver catalyst is a silver nanocrystal having a plurality of surface planes, a substantial portion of which is defined by Miller indices of (100). The reaction is performed by charging a suitable reactor with this silver catalyst and then feeding the reactants to the reactor under conditions to carry out the reaction. The reaction may be performed in batch, or as a continuous process that employs a recycle of any unreacted alkenes. The specific silver catalyst has unexpectedly high selectivity for epoxide products. Consequently, this general method (and its various embodiments) will result in extraordinarily high epoxide yields heretofore unattainable.

Linic, Suljo↗

Establishing Relationships Between the Geometric Structure and Chemical Reactivity of Alloy Catalysts Based on Their Measured Electronic Structure

While it is fairly straightforward to predict the relative chemical reactivity of pure metals, obtaining similar structure-performance relationships for alloys is more challenging. In this contribution we present experimental analysis supported with quantum chemical DFT calculations which allowed us to propose a simple, physically transparent model to predict the impact of alloying on the local electronic structure of different sites in alloys and on the local chemical reactivity. The model was developed through studies of a number of Pt alloys. The central feature of the model is that hybridization of d-orbitals in alloys does not lead to significant charge transfer between the constituent elements in the alloy, and therefore the width of the local density of d-states projected on a site, which is easily calculated from tabulated parameters, is an excellent descriptor of the chemical reactivity of the site.

36 MATERIALS SCIENCE↗

Communications: Developing relationships between the local chemical reactivity of alloy catalysts and physical characteristics of constituent metal elements

We have used X-ray absorption spectroscopy and quantum chemical density functional theory calculations to identify critical features in the electronic structure of different sites in alloys that govern the local chemical reactivity. The measurements led to a simple model relating local geometric features of a site in an alloy to its electronic structure and chemical reactivity. The central feature of the model is that the formation of alloys does not lead to significant charge transfer between the constituent metal elements in the alloys, and that the local electronic structure and chemical reactivity can be predicted based on physical characteristics of constituent metal elements in their unalloyed form.

37 INORGANIC, ORGANIC, PHYSICAL, AND ANALYTICAL CH↗