Mark Maroncelli

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Mark Maroncelli (born December 1957) is an American chemist, currently serving as professor of chemistry at the Pennsylvania State University, [1] where he also coordinates the Chemistry Department's undergraduate program.

Contents

Career

Mark received a B.S. degree in chemistry from Williams College (1979) and a Ph.D. degree in physical chemistry from the University of California, Berkeley (1983). He spent the next four years as a postdoctoral researcher at two institutions, Oregon State University (1984–1985) with Prof. Joseph W. Nibler and the University of Chicago (1985–1987) with Prof. Graham R. Fleming.

In 1987 Mark received his first academic appointment, as assistant professor at the Pennsylvania State University (1987–1993). In 1993 he was appointed associate professor, and in 1997 he was made a full professor.

Research

Prof. Maroncelli's research interests include solvation and solvent effects on chemical reaction, liquid-phase dynamics, electron and proton transfer reactions, supercritical fluids and expanded liquids, ionic liquids, ultrafast spectroscopy, and computer simulation.

Maroncelli’s research seeks to develop a fundamental understanding of the molecular nature of solvation and how it affects chemical reactions taking place in solution. Solvation involves the interactions between dissolved molecules (solutes) and molecules of the solvent. Favorable arrangements of solvent molecules around the solute lower its energy, which leads to dissolution. The interactions involved are typically very rapid, taking place in as short a time as 1 ps (10^-12 s). Because the key steps in most chemical reactions also occur on these fast time scales, time-dependent aspects of solvation partly determine how a solvent influences the rate and course of chemical reactions. Maroncelli uses ultrafast spectroscopic techniques in combination with modern computational-chemistry methods to observe, analyze, and predict the solvation process and its impact on the chemical steps that occur during the particular reaction being investigated.

Maroncelli’s recent research has explored the nature of solvation in novel solvents such as supercritical fluids, gas-expanded liquids, and ionic liquids. Comparing model reactions such as isomerization, electron transfer, and proton transfer in these novel solvents with such reactions in conventional liquids enables his research team to test and extend the current understanding of solvent-reaction coupling. These studies have potential applications in technical chemistry, synthetic chemistry, and cell biology. [2]

Awards and honors [1]

Related Research Articles

Acid–base reaction Chemical reaction

An acid–base reaction is a chemical reaction that occurs between an acid and a base. It can be used to determine pH. Several theoretical frameworks provide alternative conceptions of the reaction mechanisms and their application in solving related problems; these are called the acid–base theories, for example, Brønsted–Lowry acid–base theory.

Solvent Substance dissolving a solute resulting in a solution

A solvent is a substance that dissolves a solute, resulting in a solution. A solvent is usually a liquid but can also be a solid, a gas, or a supercritical fluid. Water is a solvent for polar molecules and the most common solvent used by living things; all the ions and proteins in a cell are dissolved in water within the cell.

Solvation Association of molecules of a solvent with molecules or ions of a solute

Solvation describes the interaction of solvent with dissolved molecules. Both ionized and uncharged molecules interact strongly with solvent, and the strength and nature of this interaction influence many properties of the solute, including solubility, reactivity, and color, as well as influencing the properties of the solvent such as the viscosity and density. In the process of solvation, ions are surrounded by a concentric shell of solvent. Solvation is the process of reorganizing solvent and solute molecules into solvation complexes. Solvation involves bond formation, hydrogen bonding, and van der Waals forces. Solvation of a solute by water is called hydration.

An electrolyte is a medium containing ions that is electrically conducting through the movement of those ions, but not conducting electrons. This includes most soluble salts, acids, and bases dissolved in a polar solvent, such as water. Upon dissolving, the substance separates into cations and anions, which disperse uniformly throughout the solvent. Solid-state electrolytes also exist. In medicine and sometimes in chemistry, the term electrolyte refers to the substance that is dissolved.

Solubility Capacity of a substance to dissolve in a solvent in a homogeneous way

In chemistry, solubility is the ability of a substance, the solute, to form a solution with another substance, the solvent. Insolubility is the opposite property, the inability of the solute to form such a solution.

Aqueous solution Solution in which the solvent is water

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Implicit solvation is a method to represent solvent as a continuous medium instead of individual “explicit” solvent molecules, most often used in molecular dynamics simulations and in other applications of molecular mechanics. The method is often applied to estimate free energy of solute-solvent interactions in structural and chemical processes, such as folding or conformational transitions of proteins, DNA, RNA, and polysaccharides, association of biological macromolecules with ligands, or transport of drugs across biological membranes.

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References

  1. 1 2 "Maroncelli Research Group | Experimental and Computational Solution Dynamics | Penn State University". web.archive.org. April 13, 2012. Archived from the original on 2012-04-13.
  2. "Maroncelli Research Group | Experimental and Computational Solution Dynamics | Publications". web.archive.org. April 24, 2014. Archived from the original on 2014-04-24.
  3. "Joe Henry Hidebrand Award report".
  4. "The Physical Chemistry Division of the American Chemical Society".
  5. "Humboldt Research Award Report".