Glênisson de Oliveira
 
Research at the de Oliveira Group
The de Oliveira group conducts theoretical and computational research that is multidisciplinary in nature.  In the last four years, seventeen undergraduate students have participated in research in our laboratory.  Biology, physics and chemistry majors (with interest in physical, inorganic, or biological subfields) have been involved in projects relevant to their own majors.  Additionally, two high school students have participated.  In the last four years we have been supported by Rhode Island College Faculty Research Funds,  Faculty Development Funds, INBRE (NIH), EPSCoR (NSF), MRI (NSF), and Title II Partnership Grant (RIOHE).
 
Computational and Theoretical Chemistry
In the de Oliveira group, our main area of research is theoretical chemistry.  Historically, this label is distinct from “computational chemistry” in that the former includes the development of new methods and theories, while the latter consists of the use of existing models to help elucidate practical issues in chemical fields.  In the area of methods development, our recent efforts have been focused on the choice of mathematical functions (basis sets) used in approximate solutions of the Schrödinger equation (ab initio methods).  We have modified existing basis sets to efficiently and accurately determine the infinite basis set limits for physical properties of molecules and molecular clusters.   In one case, our method became part of standard computational chemistry packages, leading to some 300 citations to a single paper.  Given the fact that quantum mechanical calculations are particularly expensive, and simply unattainable for large systems, part of our effort is geared towards the development of models based on classical physics.  More specifically, we are interested in models that explicitly account for electrostatic contributions to non-covalent interactions, including the effect of polarizabilities, hyperpolarizabilities, and high order terms of the permanent moment tensor (i.e. beyond dipole moments).  Models we develop are used to study specific chemical problems of interest to us, but they serve as potential tools for other unrelated studies.
 
Physical, Inorganic, and Bioinorganic Chemistry
From a chemical perspective, the phenomena in which we are interested are associated with non-covalent interactions, and our studies use existing and newly developed tools of computational chemistry.  Some of the specific chemical problems we address involve weak interactions and clustering phenomena for small molecules – such studies are typically put under the umbrella of “physical chemistry,” which is our area of expertise.  On the other hand, many non-covalent interactions involve metals in coordination complexes and in metalloproteins, as well as ionic solids.  Those are traditionally classified as “inorganic chemistry.”  Some of the questions we ask are the following:  Can we account for ligand field splitting energy in coordination complexes, without appealing to the “quantum mechanical concept” of orbitals? (i.e. using only classical physics)  How can ionic solids, with high covalent character be modeled accurately, not using ideas derived from molecular orbital theory?  What is intrinsically and physically different between ionic compounds of high ionic or high covalent characters?  What is the effect of metal replacement in certain metalloproteins that have been associated with cancer?  What is the metal’s role in protein activity and the catalystic mechanisms?  The last questions are biological or bioinorganic in nature.
 
 
Computational, Inorganic,
and Physical Chemistry