*Rossini Group May 2020: (Top Row) Rick Dorn, Amrit Venkatesh, Scott Carnahan, Yunhua Chen, (Middle Row) Viraj Wijesekara, Mike Hanrahan, Matt Ryan, Cameron Jensen, (Bottom Row) Aaron Rossini, Kipper Riemersma.
The Rossini Group Overview
Welcome to the home page for the Rossini research group in the Department of Chemistry of Iowa State University. We are an experimental physical chemistry research group interested in the characterization of inorganic materials, catalysts and pharmaceuticals. The primary tool we use to accomplish this is solid-state nuclear magnetic resonance (NMR) spectroscopy.
To see some photos of our labs and facilities please visit the Facilities page.
If you are interested in joining our group please email Professor Rossini at email@example.com!
12/2020 – Rick’s paper Structure Determination of Boron-Based Heterogeneous Catalysts for Oxidative Dehydrogenation With Ultra-High Field 35.2 T 11B Solid-State NMR Spectroscopy is out now in ACS Catalysis. This paper was part of an ongoing collaboration with Ive Herman’s group. Congrats to Rick and the rest of the team.
11/2020 – Congrats to Amrit Venkatesh for successfully defending his PhD! We are grateful to Amrit for all of his contributions to the group and to ISU chemistry. We wish him the best of luck in his post-doctoral position with Lyndon Emsley.
10/2020 – Amrit’s paper The Structure of Molecular and Surface Platinum Sites Determined by DNP-SENS and Fast MAS 195Pt Solid-State NMR Spectroscopy appears in Journal of the American Chemical Society. This project was a nice collaboration with the groups of Christophe Coperet (ETH Zurich) and Anne Lesage (ENS Lyon). We used fast MAS and 1H detection and DNP to obtain 195Pt solid-state NMR spectra of silica-supported platinum compounds. Congrats to Amrit and the rest of the team!
08/2020– Congrats to Amrit on publication of his paper t1-Noise Eliminated Dipolar Heteronuclear Multiple Quantum Coherence Solid-State NMR Spectroscopy in Phys. Chem. Chem. Phys. Amrit has developed a set of modified D-HMQC pulse sequences that remove t1-noise and provide improved sensitivity for proton detection of unreceptive nuclei such as 17O, 25Mg and 35Cl. Check it out!
07/2020 – Congrats to Michael Hanrahan for completing his PhD. We will miss Mike and are grateful for all of the contributions he made to the lab. We wish him the best of luck in his next position at Kansas Analytical Services.
04/2020 – Congratulations to Viraj Wijesekara for successfully defending his MSc thesis. We wish Viraj the best in his PhD studies at University of Florida and are grateful for his contributions to the group.
Viraj and Amrit’s paper Fast Acquisition of Proton Detected HETCOR Solid‐State NMR Spectra of Quadrupolar Nuclei and Rapid Measurement of NH Bond Lengths by Frequency Selective HMQC and RESPDOR Pulse Sequences is published in Chemistry a European Journal. This paper was in collaboration with Joe Lubach and Karthik Nagapudi (Genentech) and Ivan Hung, Zhehong Gan and Peter Gor’kov (NHMFL). The paper demonstrates modified HMQC and RESPDOR experiments that use frequency selective excitation pulses to preserve 1H magnetization in between scans and reduce recycle delays. Check it out if you are interested in speeding up your 14N, 17O and 35Cl solid-state NMR experiments.
03/2020 – Congratulations to Amrit Venkatesh for winning the prestigious Ritchey Travel Award at the Experimental NMR Conference!
Yunhua Chen’s paper The Surface Termination of CsPbBr3 Perovskite Quantum Dots Determined by Solid-State NMR Spectroscopy is published in Journal of the American Chemical society. This paper was in collaboration with Sara Smock and Richard Brutchey (University of Southern California). Anne Flintgruber, a participant in the Ames Lab Summer Laboratory Intern (SULI) and Fred Perras also contributed. In this paper Yunhua used 1H, 14N, 133Cs and 207Pb solid-state NMR experiments to demonstrate that the surfaces of CsPbBr3 nanoparticles are Cs terminated with substitution of some surface Cs for cationic ammonium ligands. Congrats to Yunhua and all of the other authors!
02/2020 – Aaron is awarded a 2020 Sloan Research Fellowship. Thanks to all of the members of my group for their hard work that made this award possible.
It was a great month for 11B solid-state NMR spectroscopy in the group.
Rick Dorn and Brijith Thomas publish the paper B‐MWW Zeolite: The Case Against Single‐Site Catalysis in Angewandte Chemie International Edition. This paper was in collaboration with Prof. Ive Hermans group at University of Wisconsin – Madison. Congrats to Rick and Brijith and thanks to Ive’s group for the nice collaboration!
Rick’s paper Identifying the Molecular Edge Termination of Exfoliated Hexagonal Boron Nitride Nanosheets with Solid-State NMR Spectroscopy and Plane-Wave DFT Calculations is published in Chemistry of Materials. In this paper Rick used 11B, 14N (with fast MAS) and 15N (with DNP) solid-state NMR experiments and plane-wave DFT calculations to determine the molecular structure of the edges of hexagonal boron nitride. Congrats to Rick and the other members of the team!
12/2019 – Amrit’s paper Suppressing 1H Spin Diffusion in Fast MAS Proton Detected Heteronuclear Correlation Solid-State NMR Experiments is published in Solid State Nuclear Magnetic Resonance. This paper demonstrates some ways to suppress 1H spin diffusion and preserve spatial information in 2D HETCOR spectra. Al(ORF)3 (RF = C(CF3)3) activated silica: a well-defined weakly coordinating surface anion appears in Chemical Science. This paper was lead by the group of Matt Conley at UC Riverside. Amrit performed some nice 2D 1H-27Al NMR experiments that help to define the structure of a surface supported aluminum compound. Way to go Amrit!
11/2019 – The paper Silicene, Silicane, or Siloxene? Characterizing Silicon Nanosheets from Deintercalated Calcium Disilicide is published in Chemistry of Materials. This paper was lead by Matt Panthani’s group (ISU CBE). Mike obtained performed some nice 1H and 29Si SSNMR experiments that confirm the 2D silicane sheets consist of singly protonated silicon atoms. Congrats Mike!
We welcome new graduate student Cameron Jensen (co-advised with Prof. Wenyu Huang) to the group.
10/2019 – Rick’s paper Investigating the Microstructure of Poly(Cyclosilane) by 29Si Solid-State NMR Spectroscopy and DFT Calculations appears in Chemistry of Materials. This paper was a collaboration with Rebekka Klausen’s group at Johns Hopkins. Congrats Rick!
Synthesis and Characterization of Silica Supported Boron Oxide Catalysts for the Oxidative Dehydrogenation of Propane appears in the Journal of Physical Chemistry C. In this paper Brijith Thomas used 1D and 2D 11B solid-state NMR experiments to characterize boron oxide and hydroxide species on silica that act as catalysts for the oxidative dehydrogenation of propane. This paper was in collaboration with Ive Herman’s group at University of Wisconsin-Madison.
09/2019 – Amrit and Aaron attend the Alpine Conference on Magnetic Resonance in Solids. Amrit gives a round-table talk on Fast MAS, 1H detected methods for unreceptive nuclei. Aaron gave a talk on DNP-enhanced solid-state NMR and received the Caldarelli Prize in Magnetic Resonance for Young Investigators.
08/2019 – Mike and Yunhua’s paper Probing the Surface Structure of Semiconductor Nanoparticles by DNP SENS with Dielectric Support Materials appears in Journal of the American Chemical Society. This paper shows improved sample preparation protocols for DNP NMR experiments on semiconductor nanoparticles. With DNP we were able to perform 2D NMR experiments on CdS, Cd2P3 and silicon nanoparticles. This work was in collaboration with Javier Vela, Brandi Cossairt and Nate Neale. Congrats to Mike and Yunhua!
07/2019 – New papers are online. Scott’s paper Magic Angle Spinning Dynamic Nuclear Polarization With Radicals Created by γ-Irradiation appears in The Journal of Physical Chemistry Letters. In collaboration with the group of Dr. James Wishart (Brookhaven National Lab) we show that γ-irradiation can be used to create radical centers for polarizing nuclear spins in materials such as quartz and glucose. Congrats to Scott and the rest of the team!
The paper Ambient Synthesis of Coordination Polymer Nanomaterials by in situ Heterogeneous Metal/Ligand reactions (HetMet) appears in Nanoscale. This paper was lead by the group of Prof. Martin Thuo (ISU Materials Science and Engineering). Brijith used 1H, 13C and 71Ga SSNMR to characterize the structures of coordination polymers. Congrats Brijith!
Computationally-driven discovery of 2D MBene layers in the family of LiNiB polymorphs appears in Angewandte Chemie. This paper was lead by Prof. Julia Zaikina’s group (ISU Chemistry). Scott obtained some nice fast MAS 11B and 7Li SSNMR spectra of different lithium nickel borides.
06/2019 – We welcome Anne Flintgruber to the lab. Anne is participating in the Ames Lab Summer Undergraduate Laboratory Intern (SULI) program.
The Comment on “Chirality-Induced Electron Spin Polarization and Enantiospecific Response in Solid-State Cross-Polarization Nuclear Magnetic Resonance” appears in ACS Nano. In the Comment we argue that there are no chirality-induced effects on CPMAS NMR signal intensities. Rather the effects observed in the original article can likely be attributed to the fact that T1 widely varies from batch to batch of a compound and the NMR spectra in the original article were recorded with improper recycle delays of less than 5 x T1 of the slowest relaxing enantiomer. See our Comment for more details.
05/2019 – A new paper appears in the Molecular Pharmaceutics. David and Viraj’s article Rapid Characterization of Formulated Pharmaceuticals Using Fast MAS 1H Solid-State NMR Spectroscopy describes how fast MAS enables 1H NMR experiments to rapidly detect active pharmaceutical ingredients in tablets. This work was performed in collaboration Joe Lubach and Karthik Nagapudi at Genentech. Congrats to David, Viraj and the rest of the team!
Matt Ryan was recently awarded a prestigious Goldwater Scholarship and a Spedding Scholarship through ISU. Way to go Matt!
01/2019 – We are pleased to welcome Camaryn Mohan to the group as an undergraduate researcher through the ISU Honors program.
12/2018 – Two new papers appear in the Journal of the American Chemical Society. Scott’s article Probing O-H Bonding Through Proton Detected 1H-17O Double Resonance Solid-State NMR Spectroscopy describes the application of fast MAS and 1H detection to obtain 2D 1H-17O NMR spectra and measure O-H bond lengths and O-H J-couplings. Congrats Scott! Brijith’s article Probing the Transformation of Boron Nitride Catalysts under Oxidative Dehydrogenation Conditions describes the characterization of boron nitride ODH catalysts with 11B solid-state NMR spectroscopy. This work was performed in collaboration with Ive Hermans group at University of Wisconsin-Madison. Congrats to Brijith and the rest of the team!
11/2018 – We welcome Rick Dorn to the group as a new graduate student.
10/2018 – Mike’s paper Sensitivity-Enhanced 207Pb Solid-State NMR Spectroscopy for the Rapid, Non-Destructive Characterization of Organolead Halide Perovskites appears in Chemistry of Materials. This work is the result of an ongoing collaboration with Prof. Javier Vela’s group. Congrats to Mike and the rest of the team!
09/2018 – Several new papers are published. A short perspective article Materials Characterization by Dynamic Nuclear Polarization Enhanced Solid-State NMR Spectroscopy appears in J. Phys. Chem. Lett. Open-Resonance-Assisted Hydrogen Bonds and Competing Quasiaromaticity appears in the J. Org. Chem and was a collaboration lead by Prof. Brett Vanveller’s group. Expanding the I-II-V Phase Space: Soft Synthesis Investigation of Polytypic Ternary and Binary Zinc Antimonides appears in Chemistry of Materials and was a collaboration lead by Prof. Javier Vela’s group. Amrit and Yunhua obtained 7Li and 121Sb NMR spectra of LiZnSb. Probing Surface Defects of InP Quantum Dots Using Phosphorus Kα and Kβ X-ray Emission Spectroscopy was a collaboration lead by Prof. Brandi Cossairt and Prof. Gerald Seidler at the University of Washington. Amrit obtained some nice fast MAS 31P NMR spectra of InP quantum dots.
07/2018 – The group attends the Rocky Mountain Conference on Magnetic Resonance. Aaron Gives a talk on fast MAS methods and DNP and the other group members give poster presentations.
06/2018 – Amrit’s paper Enhancing the Sensitivity of Solid-State NMR Experiments with Very Low-Gyromagnetic Ratio Nuclei with Fast MAS and Proton Detection appears in the Journal of Physical Chemistry A. Rare Earth Arylsilazido Compounds with Inequivalent Secondary Interactions appears in Chemical Communications. This paper was lead by the Sadow group at ISU and Amrit obtained some nice 89Y NMR spectra.
We welcome Rafael Blome Fernandez and Rick Dorn to the research group as summer research students.
05/2018 – Congrats to Dr. David Hirsh on his new position at Boehringer Ingelheim in Connecticut! Aaron attends the 59th ENC in Orlando and gives a talk describing fast MAS solid-state NMR methods.
02/2018 – Congrats to Amrit Venkatesh who was awarded the prestigious Brown Graduate Fellowship from Iowa State.
Two new papers are out. Li Zhao’s paper Characterization of Pharmaceutical Cocrystals and Salts by Dynamic Nuclear Polarization-Enhanced Solid-State NMR Spectroscopy appears in Crystal Growth and Design. This paper results from a collaboration with Dr. Joe Lubach and Dr. Karthik Nagapudi from Genentech, Inc.
"Modulating Reactivity and Selectivity of 2‑Pyrone-Derived Bicyclic Lactones through Choice of Catalyst and Solvent"appears in ACS Catalysis. This paper was lead by Prof. Brent Shanks group (ISU Chemical and Biological Engineering). Matt Ryan obtained some nice 1D and 2D 1H, 13C and 27Al solid-state NMR spectra for the paper. Congrats Matt!
01/2018 – We are happy to welcome Dr. David Hirsh to the group. David just completed his PhD with Rob Schurko at the University of Windsor.
12/2017 – Two new papers are out. Michael Hanrahan’s paper, Characterization of Silicon Nanocrystal Surfaces by Multidimensional Solid-State NMR Spectroscopy appears in Chemistry of Materials. Congrats Mike! This paper was the result of a collaboration with the groups of Prof. Theresa Windus (ISU) and Dr. Nathan Neale (NREL DOE Lab). A new review article written by Dr. Li Zhao, DNP-Enhanced Solid-State NMR Spectroscopy of Active Pharmaceutical Ingredients appears in Magnetic Resonance in Chemistry.
11/2017 – Anuradha Viraj Wijesekara and Yunhua Chen (co-advised with Prof. Javier Vela) join the group as graduate students.
10/2017 – Congratulations to Dr. Li Zhao on his new position at Voxalytics in Germany. We will miss Li and wish him good luck in his new career.
09/2017 – A new paper Enhancing the Resolution of 1H and 13C Solid-State NMR Spectra by Reduction of Anisotropic Bulk Magnetic Susceptibility Broadening is out in the journal Physical Chemistry Chemical Physics. This paper demonstrates that 2D HETCOR experiments can be used to directly improve the resolution of 1H and 13C solid-state NMR spectra by reducing the inhomogeneous ABMS broadening. This work was performed in collaboration with Prof. Eric Munson (University of Kentucky).
08/2017 – We are pleased to welcome Dr. Brijith Thomas to the group as a post-doctoral fellow.
07/2017 – A new paper The Solvent-Solid Interface of Acid Catalysts Studied by High Resolution MAS NMR is out in the Journal of Physical Chemistry C. This work was performed in collaboration with Dr. Robert Johnson and Prof. Brent Shanks (ISU).
06/2017 – A new paper, Argentation Gas Chromatography Revisited: Separation of Light Olefin/Paraffin Mixtures Using Silver-based Ionic Liquid Stationary Phases, is published in Journal of Chromatography A in collaboration with Professor Jared Anderson (ISU). In this paper Amrit obtained 109Ag solid-state NMR spectra of some silver ionic liquids using fast magic angle spinning and proton detection.
06/2017 – Some new articles from Aaron’s post-doc work with Lyndon Emsley are published. A paper in Journal of the American Chemical Society in collaboration with Christophe Copéret (ETH Zurich) describes the characterization of trivalent surface grafted organometallic complexes with DNP enhanced NMR. A paper in the Journal of Physical Chemistry C describes the application of DNP enhanced NMR for the characterization of calcium silicate cement materials. This paper was in collaboration with Paul Bowen (EPFL).
05/2017 – We are pleased to welcome Dr. Li Zhao to the group as a post-doctoral fellow.
04/2017 – A new paper Proton Detection of MAS Solid-State NMR Spectra of Half-Integer Quadrupolar Nuclei is available in Solid State Nuclear Magnetic Resonance. Also, congratulations to Mike and Amrit who received scholarships/awards from the Chemistry Department. Both Scott and Amrit were named as finalists for the Cotton-Uphaus Award. Congratulations to Amrit for winning the Cotton-Uphaus Award!
03/2017 – A new perspective article Lead Halide Perovskites: Challenges and Opportunities in Advanced Synthesis and Spectroscopy is available in ACS Energy Letters. This work was a collaboration with Prof. Javier Vela and Prof. Emily Smith. A video summarizing the perspective can also be viewed here.
01/2017 – A couple of new papers are out. "Indirect Detection of Infinite-Speed MAS Solid-State NMR Spectra" appears in the Journal of Magnetic Resonance and was a collaboration with Dr. Fred Perras and Dr. Marek Pruski (Ames Lab/ISU). "Transfer Hydrogenation Activity over Sodium-Modified Ceria: Enrichment of Redox Sites Active for Alcohol Dehydrogenation" appears in the Journal of Catalysis and was a collaboration with Dr. Igor Slowing’s group (Ames Lab/ISU).
01/2017 – We are pleased to welcome Matt Ryan to the group. Matt is an undergraduate student researcher who is part of the ISU University Honors program.