Waveguide ChirpedPulse Fourier Transform Microwave Spectroscopy of 2

Background • Methoxymethanol: predicted to be in the ISM – Hays et al. •

Computational Chemistry gg’tt 0 cm-1 Debye gg’tg 440 cm-1 gg’tg’ 530 cm-1 |μa| 2.

Experimental Set Up • 8. 7 – 13. 5 GHz • 13. 5 –

2 -Ethoxyethanol 1 M shots -20 o. C 7 m. Torr 4 μs FID

Triples Fitter • Predict spectrum from an initial guess • Select three transitions expected

EEO GS Calculated Triples Fitter Current A (MHz) 8761. 148 8701. 3 8795. 65(41)

Future Work Excited State Fit: Possible Ethyl Torsion EEO ES Current A (MHz) 8759.

Acknowledgements Dr. Steven Shipman New College of Florida Bri Gordon National Science Foundation Benjamin

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Waveguide Chirped-Pulse Fourier Transform Microwave Spectroscopy of 2 -Ethoxyethanol Maria A. Phillips, Steven Shipman New College of Florida

Background • Methoxymethanol: predicted to be in the ISM – Hays et al. • 2 -Methoxyethanol: Caminati et al. • 2 -Ethoxyethanol: Slightly larger, no previous MW Work Hays B. M. ; Widicus Weaver S. L. J. Phys. Chem. A, in press 2013 Caminati, W. ; Meyer, R. ; Smith, Z. Chemical Physics, 1986, 110, 67 -82

Computational Chemistry gg’tt 0 cm-1 Debye gg’tg 440 cm-1 gg’tg’ 530 cm-1 |μa| 2. 033 |μb| 1. 5781 |μc| 0. 083 gg’g’t 630 cm-1 El-Hefnawy, M. ; Sameshima, K. ; Matsushita, T. ; Tanaka, R. ; Chemical Society of Japan, 2006, 79, 845 – 856 Tafazzoli, M. ; Jalil, S. ; Theoretical Chemistry Accounts, 2002, 107, 162 – 172

Experimental Set Up • 8. 7 – 13. 5 GHz • 13. 5 – 18. 3 GHz • 18. 0 – 26. 5 GHz

2 -Ethoxyethanol 1 M shots -20 o. C 7 m. Torr 4 μs FID

Triples Fitter • Predict spectrum from an initial guess • Select three transitions expected to be present (used for fitting) • Select another 10 – 20 transitions also expected to be present (used for scoring) • Assign experimental peaks to fitting transitions, run SPFIT then SPCAT and score the resulting spectrum • Repeat for many combinations of experimental peaks and rank the results

EEO GS Calculated Triples Fitter Current A (MHz) 8761. 148 8701. 3 8795. 65(41) B (MHz) 1612. 882 1631. 52 1630. 98(75) C (MHz) 1457. 318 1472. 37 1473. 45(70) ΔJ (k. Hz) 0. 5174 0. 496318(187) ΔJK (k. Hz) -4. 700 -4. 45233(141) ΔK (k. Hz) 459. 77 434. 271( 88) δJ (k. Hz) 0. 114 0. 1057660(156) δK (k. Hz) 3. 314 3. 16146( 78) ΦJ(Hz) -- -- -0. 7612(82)E-03 ΦKJ(Hz) -- -- -0. 07091(133) φJ(Hz) -- -- 0. 17192(167)E-03 Fit RMS (k. Hz) -- -- 57 Highest J -- -- 113 Lines Fit -- -- 330 B 3 LYP/6 -311++G(d, p)

2 -Ethoxyethanol

Future Work

Future Work Excited State Fit: Possible Ethyl Torsion EEO ES Current A (MHz) 8759. 7828(78) B (MHz) 1625. 16201(159) C (MHz) 1473. 57295(148) ΔJ (k. Hz) 0. 3724( 47) ΔJK (k. Hz) 11. 460( 57) ΔK (k. Hz) 73. 427(124) δJ (k. Hz) 0. 24220( 48) δK (k. Hz) 5. 008( 89) Fit RMS (k. Hz) 94 Highest J 29 Lines Fit 109

Acknowledgements Dr. Steven Shipman New College of Florida Bri Gordon National Science Foundation Benjamin Rooks Office of Naval Research Christian Metzger Ian Finneran Benjamin Reinhold Erin Kent Morgan Mc. Cabe

Expanded View

Flow – Through Chiller System