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New Applications of Broadband Rotational Spectroscopy. 1. Wednesday 18 th April 2012 ERC Starting Grant Presentation Nicholas R. Walker. (Left) The CP-FTMW spectrometer re-located to Newcastle University (Right) Some components of the instrument.
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New Applications of Broadband Rotational Spectroscopy 1. Wednesday 18th April 2012 ERC Starting Grant Presentation Nicholas R. Walker (Left) The CP-FTMW spectrometer re-located to Newcastle University (Right) Some components of the instrument.
Wednesday 18th April 2012, ERC Proposal Presentation, Nicholas R. Walker 2. Career Background 1996-2003 Worked at 5 different institutions in Europe and North America. 48 peer-reviewed articles and achieved an h-index of 21. 2003-2011 Royal Society University Research Fellowship, University of Bristol. 2012 Susanna Stephens, Nicholas Walker and the CP-FTMW spectrometer in Newcastle.
8000 12000 16000 Frequency / MHz Wednesday 18th April 2012, ERC Proposal Presentation, Nicholas R. Walker 3 The Broadband Advantage 1946 - First high resolution microwave spectroscopic measurements. 1981 – cavity FT-MW spectroscopy (Balle and Flygare). 2006 – Construction of the chirped-pulse Fourier transform microwave spectrometer (Pate1). Frequency / MHz 1. G.G. Brown et al., Rev. Sci. Instr. 79, 053103(2008)
8000 10000 12000 14000 16000 18000 Frequency / MHz Wednesday 18th April 2012, ERC Proposal Presentation, Nicholas R. Walker 4. The Broadband Advantage 13850 13860 13870 Frequency / MHz CP-FTMW* BalleFlygare FTMW 1MHz Measurement bandwidth 11GHz 48 minutes Time required for data acquisition 14 hours * G.G. Brown et al., J. Mol. Spec., 238 200(2006)
Wednesday 18th April 2012, ERC Proposal Presentation, Nicholas R. Walker 5. Objectives Address problems outside of traditional boundaries of microwave spectroscopy. Pd, C2H4, C2H2 Chemical analysis Role of metals in biochemistry Metal ion solvation Methodology Infrared spectroscopy Microwave spectroscopy Theory
Wednesday 18th April 2012, ERC Proposal Presentation, Nicholas R. Walker 6. Theme 2 – Microscopic Ion Solvation Ni+(CO2)5 Ni+(CO2)4 Ni+(CO2)3 N.R. Walker, R.S. Walters, G.A. Grieves and M.A. Duncan, J. Chem. Phys. 121, 10498-10507 (2004) N.R. Walker, R.R. Wright and A.J. Stace, J. Am. Chem. Soc.121, 4837-4844 (1999)
Wednesday 18th April 2012, ERC Proposal Presentation, Nicholas R. Walker 7. Theme 2 – Microscopic Ion Solvation H2OAgCl:N.R. Walker and co-workers, Angew. Chem. Int. Ed. 49, 181-183 (2010) H2OAgF: N.R. Walker and co-workers, J. Mol. Spectrosc. 267, 163-168 (2011) A. Mizoguchi, Y. Ohshima and Y. Endo, J. Chem. Phys.135, 064307 (2011)
Strategic Collaborations 8. World Europe Key Collaborators Other Competitors BH Pate (Virginia) W Jaeger (Alberta) M Schnell (Hamburg) MA Duncan (Georgia) BJ Howard, SR MacKenzie (Oxford) Tew, Legon, Western (Bristol) Alonso (Valladolid) Endo (Tokyo) DJ Tozer (Durham)
9. Wednesday 18th April 2012, ERC Proposal Presentation, Nicholas R. Walker Concluding Remarks • PI has an outstanding track record of success achieved through work at 5 different institutions in the U.K. and North America. • State-of-the-art, globally unique instrument proven through many published works since mid-2010. • Wide range of problems of contemporary importance. • Expansive programme can only be pursued because of the speed and power of CP-FTMW spectroscopy. • Newcastle University have committed funding for a postgraduate studentship to the proposed work. I will welcome questions. Thank you for your attention.
Wednesday 18th April 2012, ERC Proposal Presentation, Nicholas R. Walker Theme 1 objective: Determine precisely all bond lengths and angles in isolated species of Mn(C2H4), Mn(C2H2), Mn-CCH and Mn-CH2 where M=Ni, Pd, Pt. Theme 2 objective: Determine the geometries of (H2O)nAgCl and (H2O)nAgF where n=1-6 to characterise the emerging solvent environment and identify whether the structures of these complexes follow divergent trends (with increasing n) even at these small sizes of unit. Subsequent experiments will use the same methodology to explore the microscopic solvation of CuCl, CuF, AuCl and AuF Theme 3 objective:Determine precisely bond lengths and angles in complexes formed between the ionic copper atom of a copper chloride molecule and one or more glycine or imidazole molecules. Equivalent interactions involving alanine, histidine and cysteine will be characterised in subsequent experiments. IR and MW spectra of the complexes will be analysed to determine vibrational band shifts and characterise the structures. Theme 4 objective:Spectrometer will be coupled with gas chromatography to demonstrate new measurement dimension for the technique. The instrument will be used to distinguish the chemicals present in wine and fruit juice.
Project Plan Postdoctoral researcher Postgrad. 2 Postgrad. 3 Postgrad. 1
Postdoctoral researcher Postgrad. 2 Postgrad. 3 Postgrad. 1
Recent Results 1.914(1) Å 2.062(6) Å 2.1531(3) Å 2.0633(3) Å 40.9(13) 78.052(6) H2OCuCl rapidly inverts on the timescale of molecular rotation. H2SCuCl is rigidly pyramidal C2H4AgCl. The C=C double bond in ethene lengthens by 0.0124 Å on attaching to AgCl (Similar for CuCl) (Owing to * electron donation from C2H4 to the metal) 2.1719(9) Å 2.2724(8) Å 1.354(40) Å These studies are further described in publications; Angew. Chem. Int. Ed., 49, 181-183 (2010)J. Chem. Phys., 134, 134305 (2011) J. Chem. Phys. 135, 014307 (2011) J. Chem. Phys. 135, 024315 (2011)
Wednesday 18th April 2012, ERC Proposal Presentation, Nicholas R. Walker S.L. Stephens, D.P. Tew, V.A. Mikhailov, N.R. Walker and A.C. Legon, , J. Chem. Phys.135, 024315 (2011) C2H4 AgCl The r(C=C) bond distance is 0.013 Å longer than that found in free C2H4. r(C=C) = 1.3518(4) Å1 r(Ag-*) = 2.1719(9) Å r(Ag-Cl) = 2.2724(8) Å PtC2H4 PtC2H2 PtCCH
Wednesday 18th April 2012, ERC Proposal Presentation, Nicholas R. Walker Theme 3 – Copper Binding Sites in Enzymes What can we learn about biochemistry from gas phase spectroscopy? Molecular recognition Alonso and co-workers: Use a combination of microwave spectroscopy and high accuracy theory to spectroscopically distinguish between different conformers of amino acids and carbohydrates. e.g., alanine (left) S. Blanco et al., J. Am. Chem. Soc., 126, 11675 (2004) Conformation Zwier and co-workers: Drive changes in conformation using infrared light and measure the efficiency of the isomerisation. B.C. Dian et al., Science, 296, 2369 (2002) N-acetyl-tryptophan methyl amide
Wednesday 18th April 2012, ERC Proposal Presentation, Nicholas R. Walker Glycine Cysteine Histidine Alanine Imidazole
Wednesday 18th April 2012, ERC Proposal Presentation, Nicholas R. Walker Theme 4 - Rotational Spectroscopy Beyond the Complexity Limit • Task of assigning spectra becomes increasingly difficult when a sample contains many different chemicals. • Technology behind broadband rotational spectroscopy advancing quickly. • Broadband rotational spectroscopy distinguishes between molecules on the basis of their structure rather than their mass/charge ratio.
New Challenges and Opportunities Analysis Biology -D-fructofuranose Molecular Dynamics Syn. Anti. Conformational isomerisation of cyclopropane carboxaldehyde1 1) B.C. Dian, G.G. Brown, K.O. Douglass and B.H. Pate, Science, 320, 924 (2008)
Laser ablation source Laser ablation source informed by the designs currently used by Duncan and co-workers, Gerry and co-workers, Ziurys and co-workers.
OCAgI 10 9 107 AgI AgI CF I 3 Ag I 8000 10000 12000 14000 16000 18000 Frequency/MHz
OCAgI 109 OC AgI L 107 OC AgI L 109 107 AgI AgI Exp. Sim . OC ICF L 3 13200 13400 13600 13800 14000 14200 14400 Frequency / MHz