Chemical Structure Representation of Inorganic Salts and Mixtures of Gases: A...
ACS Presentation essay mk7
1. USING CHEMINFORMATICS
TO BETTER DESIGN OF
CHELATES TO LANTHANIDE
AND ACTINIDE COMPLEXES
Kevin Moyle╪, Dr. Shyam Vyas†, Dr. Paul Sanschagrin†, Dr.
Seth Wiggin‡, and Dr. John Brennan╪
╪Department of Chemistry and Chemical Biology, Rutgers, The State University of New Jersey,
† The Cambridge Crystallographic Data Centre Inc., Piscataway, New Jersey
‡ Cambridge Crystallographic Data Centre, 12 Union Road, Cambridge ,CB2 1EZ, United Kingdom
2. W H A T I S C H E M I N F O R M A T I C S ?
• Cheminformatics is a combination of Chemistry,
Computer and Information Science.
• Where we take information and transform it into
useful data for our intended purposes
• From this we can find trends en masse
• This is useful in drug discovery and materials
science
3. W H A T A R E W E L O O K I N G F O R ?
W H E R E F R O M ?
• Our focus is to improve the PUREX process, the
system used to separate materials generated from
nuclear reactors
• A better PUREX process enables stronger and more
selective chelates to individual metals
• Using the Cambridge Structural Database we can
access 780,000 Crystallographic Structures
• We can write a Python script to find F-block metals and
there donor atoms
4. U R A N I U M
A N A L Y S I S
• There are 4088 Uranium
Complexes in the CSD
• Most Common Donors
• Nitrogen, 13.50% ,
Average length 2.47 Å
• Carbon, 16.91%,
Average Length 2.74 Å
• Oxygen, 61.34%
5. URANIUM - ACYCLIC
OXYGENS
• Acyclic O Bonds
28.22%, average
bond length 2.07Å
• Bonds in the range
from 1.75 to 1.85Å
are largely U-O
double bonds.
• Alkoxides represent
the are 2 to 2.2Å
• Strong ligands and
mineral like structures
are in the 2.3 to 2.5Å
7. C Y C L I C
O X Y G E N B O N D S
• Cyclic Oxygens,
33.02% of all donors,
average length 2.38 Å
• Bonds less than 2Å
are bridging atoms for
different metals
• 2.3 to 2.5 Å bonds
include multidentate
ligands and bridging
atoms
9. RESEARCH
CONCLUSIONS
• As we tend to think of
shorter bond lengths as
stronger bonds, we
need to optimize size
and stability
• We can find trends for
each metal
• We need to look further
into the bond
environment
Above: LAQKAQ
10. W H AT I H AVE
L EAR N ED AN D
EXPER IEN C ED
• I’ve been introduced to
Crystallography,
Python, Materials
Science
• I’ve been in Research,
Industry and Nonprofit
Environments
• Presented my research
in the both Cambridge
and Boston
11. E M A I L : K E V I N @ M O Y L E . C O M
K E V I N . M O Y L E @ R U T G E R S . E D U
g
Questions?
Editor's Notes
Hello, I am Kevin Moyle and I’m a chemistry major at Rutgers. For the past year I’ve been an Undergraduate Researcher as a part of the Cambridge Crystallographic Data Centre and Rutgers. My research is entirely done using a computer. Specifically using Cheminformatics as the foundation of my research.
So that leads to the first question. What is Cheminformatics? Cheminformatics is the use of chemistry and information science to learn new and useful in data to better design substances. Or more aptly it is the use of data from lab results to solve various challenges. From the large sample sizes we can find trends and then we can use this information to design new compounds.
So what are we trying to figure out? The project’s goal is to better our understanding of Lanthanides and Actinides. Specifically we want to learn more about the bonding of the F-block metals. Currently the main method of separating Lanthanides and Actinides is the PUREX process. Since it was first shared 60 years ago, the commonly used solvent is a mixture of Tributyl-Phosphate and kerosene. In addition Nitritic acid is added into the mixture for separation. Our challenge is to find a new method of extraction that is more selective for each metal. We can do this by working in the Cambridge Structural Database or CSD to find Lanthanide and Actinide compounds. Then for each compound we find the specific metal and its donor atoms, from this data we can find trends for each metal.
For today we’ll focus on Uranium. These 3 atoms Nitrogen, Carbon and Oxygen represent over 90% of all donor atoms. Nitrogen is 13.5% of all donors and the average length from Uranium to the donor is 2.47Å. For Carbon, it represents 16.91% of all donors and have an average bond length of 2.74Å. This larger bond length is a result of a high concentration of metallocene bonding. For oxygen, 61.34%, we need to look further for better analysis.
First we’ll look at acyclic oxygens that bond to Uranium. Acyclic Oxygen donors make up 28.22 percent of Uranium donors and have an average bond length of 2.07 Å. As you can see there are two peak areas and a trough in the middle. The shorter lengths from 1.7 to 1.9 are mostly Uranium-Oxygen double bonds. The larger bond lengths are the result of monodentate ligands and mineral like structures.
Here are a few examples from crystallographic structures in our searches . The top left structure contains several monodentate ligands. Of note are the two triphenyl-phosphine oxides with both having a bond length of 2.34Å. On the right is a mineral-like structure that has bonds in the range of 1.8, 2.3 and 2.4Å. The inset box provides a better look at a pair of the Uranium-Oxygen double bonds with lengths near 1.8Å.
For Cyclic Oxygen there is more consistency. There are few bonds less than 2.2Å. The most common lengths are in the range of 2.35 to 2.4 and 2.45 to 2.5Å. These include a lot of bridging atoms and common ligands, (Acac and so on)
Here we have Uranium compounds with Cyclic oxygen ligands. the one on the left has Nitrate ligands similar to what we would see in the PUREX process, of note is that the Nitrato ligands have lengths in between 2.5 and 2.6Å. The complex on the right exhibits bridging oxygen ligands with lengths from 2.35 to 2.5Å.
So what have learned so far? We have found trends in bond sizes for all the Lanthanides and for Actinides that have an adaquet amount of compounds. We are looking into getting not just an understanding of the donor atoms but the atoms bonded to the donors.
I would also like to thank the CCDC for letting me have such a wonderful experience, especially my Research Supervisor Dr. Shyam Vyas.
