Watheq Al-Basheer 1,2 , Shin Y. Toh 2 , Jun Miyazaki 2,3 and Takamasa Momose 2

1. Conformational Analysis of R-(+)-3-Methylcyclopentanone by IR Spectroscopy in Para-Hydrogen Crystal Watheq Al-Basheer1,2, Shin Y. Toh2, Jun Miyazaki2,3 and Takamasa Momose2 1Dep. of Physics, King Fahd University of Petroleum and Minerals, Dhahran, Saudi Arabia 2Dep. of Chemistry, University of British Columbia, Vancouver, BC, Canada 3Dep. of Liberal Arts and Basic Sciences, College of Industrial Technology, niho, japan 69th International Symposium on Molecular Spectroscopy University of Illinois at Urbana-Champaign, Jun. 19th 2014

2. Isolation Matrix Infrared Spectroscopy • In 1954, George C. Pimentel (Berkeley) proposed using inert elements as isolation matrices due to: 1- Unreactive with entrapped molecule due to completely filled outermost shell 2- Weak forces between atoms (induced p-p) (Van der Waals forces). 3- Electron distribution in crystals close to free atoms (crystals are transparent insulators) 4- Atoms pack as close as possible (fcc structure)

3. Hydrogen Molecule (H2) para-hydrogen ortho-hydrogen I = 0 I = 1 Pure para-Hydrogen (pH2) Matrix will work as a good isolation Matrix

4. Macroscopic View of pH2 as an Isolation Matrix • Hydrogen crystal structure is hexagonal close packed (hcp) which is an ideal isolation matrix due to: • 1- Large lattice constant (~ 3.78 ᴼA). • 2- Because pH2 is light, it has large zero-point vibration • (Amplitude of vibration ~ 20% of the lattice constant). • 3- Capability to repair itself of crystal defects. • 4- Solvent cage effects are minimal Para-hydrogen crystal is a soft quantum crystal Momose et al, J. Chem. Phys. 107 (19), (1997).

5. Making & Doping para-hydrogen (pH2) crystal

6. Candidate dopant molecule (chiral R-(+)-3-Methylcyclopentanone) • R-(+)-3-Methylcyclopentanone (R3MCP) is a chiral ketone. • Exists in all living cells (drug industry applications). • Has high optical activity. • Has enough vapor pressure at room temp. • Has two different conformers (Equatorial, Axial). • Has 45 vibrational degrees of freedom (possible IR modes [70-3000 cm-1] ) W. Al-Basheer, J. Sol. Chem. 41, 1495-1506 (2012) W. Al-Basheeret al, J. Phys. Chem. A. 111(12),(2007)

7. Para-hydrogen crystal(pH2) Matrix Vs Argon and pure sample

8. Para-hydrogen crystal(pH2) Matrix Vs Argon and pure sample

9. Para-hydrogen crystal(pH2) Matrix Vs Argon and pure sample

10. Para-hydrogen crystal(pH2) Matrix Vs Argon and pure sample

11. R3MCP concentration in pH2 crystal

12. R3MCP concentration in pH2 crystal

13. R3MCP concentration in pH2 crystal

14. Summary & Conclusions • pH2 crystal is an ideal isolation matrix that can yield high resolution IR spectra of molecules due to its intrinsic nature as a cold and soft quantum crystal. • Isolation Matrix IR spectroscopy in pH2is an efficient tool to study molecular structure of polyatomic chiral molecules. • 50 ppm chiral R3MCP molecule concentration in para-hydrogen crystal has yielded the highest resolved IR spectrum. It is possible that pH2 dimers are more likely to form at higher concentrations.

15. Acknowledgements • KFUPM’s International Summer Scholarly Program (ISSP) for Generous financial support • Prof. TakamasaMomose, University of British Columbia for hosting.