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    The core of this program is the design of new functional materials (artificial metalloenzymes, heterogeneous catalysis, alloys, molecular motors), guided by insights into chemical bonding, and accompanied by the development of the modern theory of chemical bonding. In a way, the "alter-ego" title of the program is "wave-function design for new functional materials". Chemical bonding is a set of qualitative tools that always, since the time of Democritus to Kekule and to this day, enabled chemists to quickly and intuitively rationalize structures and properties materials. New materials, such as inorganic clusters or alloys, offer a wealth of new concepts of chemical bonding, which, once understood, become useful in materials design. On the methodological side, we make use of electronic structure methods, and develop multi-scale methods (problem-inspired flavors of QM/MM MC and dynamics for extensive sampling), stochastic and machine learning methods for global optimization, electron localization, and data mining techniques. However, we are a chemistry-driven, applied group, and introduce new methods only as becomes necessary.

    Over the years, this research has been powered by:
    Design of artificial enzymes.

    Enzyme evolution.

    We aim at designing catalysts that mimic natural enzymes in catalytic strategies, but catalyze reactions that interest humankind. This effort is presently fundamental. However, eventually, it might lead to unprecidented catalytic processes, green, efficient, and inexpensive, used at an industrial scale. The philosophy of this area of research is that the effort is largely done in silico, and experiment is envoked only at the end of the workflow to check theoretical predictions. Modeling of enzymes is done with atomistic and electronic insight. We develop fast techniques for mixed quantum-classical simulations and design.

    Selected References:

    Valdez, C. E.; Smith, Q. A.; Nechay, M. W.; Alexandrova, A. N.* Mysteries of metals in metalloenzymes. 2014, Acc. Chem. Res., 47, 3110-3117.

    Sparta, M.; Valdez, C. E.; Alexandrova, A. N.* Metal-dependent activity of Fe and Ni acireductone dioxygenases: how two electrons reroute the catalytic pathway. 2013 J. Mol. Biol., 245, 3007-3018. Featured on the Cover

    Sparta, M.; Ding, F.; Shirvanyants, D.; Dokholyan, N. V.;* Alexandrova, A. N.* Hybrid dynamics simula tion engine for metalloproteins. 2012 Biophys. J. 103, 767-776. PDF

    Valdez, C. A.; Alexandrova, A. N.* Why Urease is a di-Nickel Enzyme, whereas the CcrA beta-Lactamase is a di-Zinc Enzyme. 2012 J. Phys. Chem. B., DOI: 10.1021/jp302771n. PDF

    Shirvanyants, D.; Alexandrova, A. N.; Dokholyan, N. V.* Rigid substructure search, 2011, Bioin formatics, 27, 1327-1329. PDF

    Alexandrova, A. N.; Roethlisberger, D.; Baker, D.; Jorgesen, W. L. Catalytic Mechanism and Performanc e of Computationally Designed Enzymes for Kemp Elimination, J. Am. Chem. Soc., 130, 15907-15915, 2008. PDF

    Clusters, Surfaces, Catalysis

    We work on fundamental understanding of small clusters in the gas phase, and deposited on supporting surfaces. Such systems present the last frontier of inorganic chemistry, in terms of their electronic structure and chemical bonding. In addition, they are exceptioanlly promising catalysts, due to many unique electronic characteristics. Our goal is to bring electronic structure rationale to understanding such catalytic materials, interpretation of experimental data, and design of new catalysts, with the ambition to remove the traditional empiricism from the field. Catalytic processes of interest are CO and NOx oxidation. Methodology involves Density-Functional Theory and ab initio, as well as our in-house mixed quantum-classical algorithms for multi-sale simulations, and tools for finding the global minima on the potential energy surfaces of clusters.

    Selected References:

    Ha, M.-A.; Dadras, J.; Alexandrova, A. N.* Rutile-supported Pt-Pd clusters: a hypothesis regarding the stability at 50/50 ratio. 2014, ACS Catal., Special issue on computational catalysis, 4, 3570-3580.

    Shen, L.; Dadras, J.; Alexandrova, A. N.* Pure and Zn-doped Pt clusters go flat and upright on MgO(100). 2014, Phys. Chem. Chem. Phys., in press, Cover article.

    Zhang, J.; Alexandrova, A. N.* The Golden Crown: How a Single Gold Atom Boosts the CO Oxidation Catalyzed by Palladium Cluster on Titania Surfaces. 2013 J. Phys. Chem. Lett., 4, 2250-2255.

    Zhang, J.; Alexandrova, A. N.* Double Sigma-Aromaticity in a Surface Deposited Cluster: Pd4 on TiO2 (110). 2012, J. Phys. Chem. Lett., 3, 751-754. PDF

    Zhang, J.;* Sergeeva, A. P.; Sparta, M.; Alexandrova, A. N.* Photo-driven Molecular Wankel Engine B13 +. 2012 Angew. Chem. Int. Ed. 51, 8512-8515. Designated as the VIP article. PDF

    Zhang, J.; Alexandrova, A. N.* Structure, stability, and mobility of small Pd clusters on stoicheomet ric and defective TiO2 (110) surfaces. 2011, J. Chem. Phys., 135, 174702. PDF

    Huynh, M.; Alexandrova, A. N.* Persistent Covalency and Planarity in the BnAl6-n2- and LiBnAl6-n- (n=1-6) Cluster Ions. 2011, J. Phys. Chem. Lett., 2, 2046-2051. PDF

    Some Regalia:
We are on the cover of JMB 2013

We are on the cover of CPL 2012

We are on the cover of JPC A 2005

We are on the inside cover of PCCP 2012

C&E News, 2013

C&E News, 2005

We are highlighted in Nat. Nanotech 2012

We are in UCLA Today

UCLA Today again

In NY Times

Jin is in Departmental News

In Chemistry World 2014

UCLA Today on Crystal's Lindau Award

ICCB 2014 on cover of C&E News!

We are on the cover of PCCP, 2014

We are on the cover of JPC B, 2015