We are an experimental physical chemistry and materials chemistry research group interested in the intrinsic relationship between structure and properties. Bellow you can read about the following projects:
Planetary Ices (minerals on Titan, Saturn’s moon)
Crystal Engineering (pharmaceuticals, supplements, pesticides)
Defects Engineering (porous materials)
Methods and Techniques
In planetary science the term “ices” refers to volatile chemical compounds with freezing points above about 100 K, such as water, ammonia, and hydrocarbons. Surprisingly, the solid-state structures of many of these ices remain unknown. Our current focus are the ices on Titan, Saturn’s moon. At 93 K, Titan’s surface features lakes and seas made of liquid ethane, liquid methane is raining and hydrocarbons are snowing from the sky. Our goal is to mimic these hostile conditions in order to learn more about the formation of potential minerals and aerosols.
This research is relevant for several reasons. First, Titan has active rain cycle, lakes, seas and solid grounds, similar to young Earth, thus is considered to be a prebiotic laboratory on a gigantic scale. Second, in 2026, NASA will launch the New Frontiers mission and will send the Dragonfly rover to explore the surface of the moon. Understanding the landing and exploration area of the rover is of paramount importance of the mission. Laboratory models can provide most valuable insights into the structure of the surface.
Crystal engineering is a discipline that focuses on the design and synthesis of molecular crystal structures with desired properties, based on an understanding and use of intermolecular interactions, such as hydrogen bonding and coordination bonding. Currently, one of our targets is increasing of the solubility of pharmaceuticals and supplements. Many drugs exhibit rather poor aqueous solubility, which in effect results in low bioavailability. Rational changes in the crystal structure can help increase of solubility and dissolution rates. On the contrary, we aim to decrease the solubility of fungicides. Upon rain, fungicides are washed from the crops into the soil. Poorly soluble formulations would provide longer retention time, better crop protection and less contamination of the environment.
Metal-Organic Frameworks (MOFs) are materials made of organic linkers connected via inorganic ions/clusters into a porous framework. One of the main characteristics of MOFs is their crystallinity and structural order. For over decades, these structural properties have been leveraged in materials design for gas storage and separation, catalysis, sensing and other applications. In our research, we use an opposite strategy, we try to destroy the order and introduce structural defects in a controlled manner, with the goal to elicit novel properties.
Additionally, we use MOF materials to study non-conventional chemical bonding. For example, diiodine is predicted to be an excellent ligand, however, there are less than 10 reported crystal structures featuring direct bond between diiodine and metal. We use MOF open metal sited to selectively adsorb diiodine and study the resulting metal – ligand interactions.
Methods and Techniques
To understand the structure of materials it is necessary to study structural order and disorder at different length- and time-scales. In our group we use combination of methods, such as X-ray powder diffraction (crystal structure solution, Rietveld refinement, QPA), X-ray single crystal diffraction, X-ray total scattering (PDF analyses), neutron powder diffraction, inelastic and quasielastic neutron scattering, and Raman/IR spectroscopy.
We are frequent users of national large-scale facilities, such as the Advanced Photon Source (APS) at Argonne Nat Lab for synchrotron X-ray diffraction and total scattering, and the Center for Neutron Research (CNR) at NIST for neutron diffraction and spectroscopy. Our lab is equipped with a custom-build powder X-ray diffractometer with detectors originally designed for synchrotron beamlines and capability for variable-temperature and photo-diffraction measurements. Additionally, our lab is equipped with instrumentation for thermal analyses (DSC, TGA) and various spectroscopies (UV-vis, IR, NMR). We have capabilities for sample preparation and chemical syntheses (wet chemistry, schlenk lines, glovebox, etc.). Finally, we have uninterrupted access to the ManeFrame II cluster for high-performance computing.