New Applications of Broadband Rotational Spectroscopy

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.

1.

2003-2011 Royal Society University Research Fellowship, University of Bristol.

2012

1996-2003 Worked at 5 different institutions in Europe and North America. 48 peer-reviewed articles and achieved an h-index of 21.

Susanna Stephens, Nicholas Walker and the CP-FTMW spectrometer in Newcastle.

Wednesday 18th April 2012, ERC Proposal Presentation, Nicholas R. Walker

Career Background2.

1946 - First high resolution microwave spectroscopic measurements.

3

1. G.G. Brown et al., Rev. Sci. Instr. 79, 053103 (2008)

1981 – cavity FT-MW spectroscopy (Balle and Flygare).

Frequency / MHz8000 12000 16000

Frequency / MHz

2006 – Construction of the chirped-pulse Fourier transform microwave spectrometer (Pate1).

Wednesday 18th April 2012, ERC Proposal Presentation, Nicholas R. Walker

The Broadband Advantage

8000 10000 12000 14000 16000 18000Frequency / MHz

Wednesday 18th April 2012, ERC Proposal Presentation, Nicholas R. Walker

Measurement bandwidth

Time required for data acquisition

1MHz

14 hours11GHz48 minutes

Balle Flygare FTMW CP-FTMW*

* G.G. Brown et al., J. Mol. Spec., 238 200 (2006)

4.

The Broadband Advantage

13850 13860 13870Frequency / MHz

Microwave spectroscopy

Theory

Infrared spectroscopy

ObjectivesAddress problems outside of traditional boundaries of microwave spectroscopy.

Metal ion solvation

Role of metals in biochemistry

Chemical analysis

Wednesday 18th April 2012, ERC Proposal Presentation, Nicholas R. Walker

Methodology

Pd, C2H4, C2H2

5.

Theme 2 – Microscopic Ion Solvation

N.R. Walker, R.R. Wright and A.J. Stace, J. Am. Chem. Soc. 121, 4837-4844 (1999)

N.R. Walker, R.S. Walters, G.A. Grieves and M.A. Duncan, J. Chem. Phys. 121, 10498-10507 (2004)

Wednesday 18th April 2012, ERC Proposal Presentation, Nicholas R. Walker

Ni+(CO2)5

Ni+(CO2)4

Ni+(CO2)3

6.

A. Mizoguchi, Y. Ohshima and Y. Endo, J. Chem. Phys. 135, 064307 (2011)

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)

Wednesday 18th April 2012, ERC Proposal Presentation, Nicholas R. Walker7.

Theme 2 – Microscopic Ion Solvation

Key Collaborators BH Pate (Virginia)W Jaeger (Alberta)M Schnell (Hamburg)MA Duncan (Georgia)BJ Howard, SR MacKenzie (Oxford)Tew, Legon, Western (Bristol)

Other CompetitorsAlonso (Valladolid)Endo (Tokyo)

World Europe

Strategic Collaborations

DJ Tozer (Durham)

8.

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 9.

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.

Wednesday 18th April 2012, ERC Proposal Presentation, Nicholas R. Walker

Year 1 Measure and analyse MW spectra of MC2H4 and MC2H2 where M is nickel, palladium or platinum. Write automation programmes

Measure and analyse MW spectra of (H2O)nAgCl, (H2O)nAgF (where n=2,3)  Construct slit nozzle.  

  Install laser to obtain IR spectra of metal ion-solvent complexes. Obtain IR spectra of (H2O)nAgCl, (H2O)nAgF (where n=2,3)  

Year 2 Measure and analyse MW and IR spectra of MCCH, MCH2 where M=Ni, Pd, Pt.DFT calculations  

Measure MW and IR spectra of (H2O)nAgCl, (H2O)nAgF (where n=4,5,6).  DFT calculations  

Modify instrument to generate complexes containing amino acids. Measure and analyse MW and IR spectra of (gly)CuCl and (imid)CuCl.

Obtain MW and IR spectra of (gly)n CuCl, (imid)nCuCl where n=2,3.  DFT calculations

Project Plan

Postgrad. 1 Postgrad. 2 Postgrad. 3Postdoctoral researcher

Year 3 Measure and analyse MW spectra of M2C2H4, M2C2H2, M3C2H4, M3C2H2, M2CCH, M2CH2, M3CCH, M3CH2,

Measure MW and IR spectra of (H2O)nCuCl, (H2O)nCuF (where n=4,5,6)

Measure and analyse MW and IR spectra of (ala)CuCl, (cys)CuCl and (hist)CuCl. DFT calculations

Measure and analyse MW and IR spectra of (hist)nCuCl (n=2,3,4)(ala)nCuCl (n=3,4) and (cys)nCuCl. (n=3,4) 

Year 4 Thesis write-up Thesis write-up Measure and analyse MW and IR spectra of (ala)nCuCl and (cys)nCuCl. (n=1,2)

Measure MW and IR spectra of (H2O)nAuCl, (H2O)nAuF (where n=1-6)

   

Year 5     Thesis write-up Construct GC-CP-FTMW spectrometer and trial performance for analysis of wine and juice.

Postgrad. 1 Postgrad. 2 Postgrad. 3Postdoctoral researcher

  Cost Category Year 1 Year 22 Year 32 Year 42 Year 52

Total (Y1-5)2

               

Direct Costs:

Personnel:            PI 36,745 77,232 80,026 82,918 85,910 362,831Senior Staff            Post docs 47,341 50,515 53,904 57,511 61,366 270,637Students 17,324 35,860 37,116 28,756 9,883 128,939Other            Total Personnel: 101,410 163,607 171,046 169,185 157,159 762,407             

Other Direct Costs:            Equipment 136,611 140,835       277,446Consumables 48,020 28,011 28,991 30,006 31,062 166,090Travel 6,237 6,454 6,680 6,914 7,157 33,442Publications, etc            Other            Total Other Direct Costs: 190,868 175,300 35,671 36,920 38,219 476,978             

Total Direct Costs: 292,278 338,907 206,717 206,105 195,378 1,239,385Indirect Costs (overheads):

Max 20% of Direct Costs 58,456 67,781 41,343 41,221 39,076 247,877

Subcontracting Costs: (No overheads)   3,400   3,520 3,680 10,600Total Costs of project: (by year and total) 350,734 410,088 248,060 250,846 238,134 1,497,862Requested Grant: (by year and total) 350,734 410,088 248,060 250,846 238,134 1,497,862

For the above cost table, please indicate the % of working time the PI dedicates to the project over the period of the grant:

90%

Budget

H2OCuCl rapidly inverts on the timescale of molecular rotation.

H2SCuCl is rigidly pyramidal

Recent Results

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)

1.914(1) Å 2.062(6) Å 2.1531(3) Å 2.0633(3) Å

78.052(6)40.9(13)

2.2724(8) Å 2.1719(9) 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)

r(C=C) = 1.3518(4) Å1

r(Ag-*) = 2.1719(9) Å r(Ag-Cl) = 2.2724(8) Å

The r(C=C) bond distance is 0.013 Å longer than that found in free C2H4.

S.L. Stephens, D.P. Tew, V.A. Mikhailov, N.R. Walker and A.C. Legon, , J. Chem. Phys. 135, 024315 (2011)

PtC2H4 PtC2H2 PtCCH

C2H4 AgCl

Wednesday 18th April 2012, ERC Proposal Presentation, Nicholas R. Walker

What can we learn about biochemistry from gas phase spectroscopy?

Molecular recognition

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

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)

Theme 3 – Copper Binding Sites in EnzymesWednesday 18th April 2012, ERC Proposal Presentation, Nicholas R. Walker

Copper centre

Coordination environment Example

Type I (T1Cu)

2 histidine (N atoms), 1 cysteine (S atom), in trigonal planar + 1 other axial ligand

Plastocyanin

Type II (T2Cu)

Square planar coordination by N or N/O ligands Enzymes

Type III (T3Cu)

Pair of Cu centres, 3 histidine Hemocyanin

A (CuA) Pair of Cu atoms coordinate with 2 histidine, 1 methionine, backbone CO, 2 bridging cysteine ligands,

Cytochrome c-oxidase

B (CuB) 3 histidine in trigonal pyramidal Cytochrome c-oxidase

Histidine

CysteineGlycine

Imidazole

Alanine

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.

Speed Flexibility

Slit nozzle

Automated spectral assignment

Double resonance GC-CP-FTMW

Sensitivity

Separating power

Wednesday 18th April 2012, ERC Proposal Presentation, Nicholas R. Walker

New Challenges and Opportunities

Biology Analysis

Conformational isomerisation of cyclopropane carboxaldehyde1

Syn. Anti.

1) B.C. Dian, G.G. Brown, K.O. Douglass and B.H. Pate, Science, 320, 924 (2008)

Molecular Dynamics

-D-fructofuranose

Laser ablation source informed by the designs currently used by Duncan and co-workers, Gerry and co-workers, Ziurys and co-workers.

Laser ablation source

OCAgI

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CF3I

107 AgI 109 AgI

AgI

OCAgI

13200 13400 13600 13800 14000 14200 14400 Frequency / MHz

107AgI 109AgI

OCICF3

Exp.

Sim.

OC107AgI OC109AgI