1. In-situ Photolysis of Methyl Iodide in Solid Para-hydrogen and Solid Ortho-deuterium Yuki Miyamoto 1, Mizuho Fushitani 2, Hiromichi Hoshina 3, and Takamasa Momose 4 1 Division of Chemistry, Graduate School of Science, Kyoto University 2 Institute fur Experimentalphysik, Freie Universitat Berlin 3 Terahertz Sensing and Imaging Laboratory, RIKEN 4 Department of Chemistry, The University of British Columbia

2. Para-hydrogen and Ortho-deuterium Excellent matrix High resolution spectroscopy In situ photolysis Solid para-hydrogen (I=0; J=0) Solid ortho-deuterium (I=0,2; J=0) Quantum solids Different environment  the nature of quantum solids This work High resolution spectroscopy In situ photolysis in o-D 2 Small interaction Large zero-point vibration

3. Photolysis in Matrices Rare gas solids Large “Cage effect”  Recombination of CH 3 I Solid para-hydrogen Small “Cage effect”  Dissociation into CH 3 and I h h

4. Photolysis of CH 3 I in Solid Para-hydrogen CH 3 I + h (254nm)  CH 3 + I M. Fushitani et al. Chem. Phys. Lett. 356 375 (2002) Before UV After UV FTIR spectra CH 3 I ( 4 ) CH 3 ( 3 ) I (magnetic dipole transition)

5. CD 3 I/o-D 2 OPO Laser 250 nm FTIR Pre-mixed sample gas CD 3 I/o-D 2 ~ 0.02%  Experiment n-D 2 o/p = 2/1 Converter ~20K o-D 2 o/p = 99 % Deposit to BaF 2 substrate ~1mJ, 10Hz, 30min.

6. Observed FTIR Spectra Before UV After UV In situ photolysis  Small cage effect of o-D 2 wavenumber (cm -1 )   mode  4 mode  ( 2 P 1/2  2 P 3/2 )

7. Spectrum of CD 3  vibrational transition of CD 3 in p-H 2 in o-D 2 wavenumber (cm -1 ) Linewidth in p-H 2 ~0.1 cm -1 in o-D 2 ~0.2 cm -1 Nevertheless, narrow enough for high resolution spectroscopy. Larger concentration of p-D 2

8. Rotational Constants rotation Reduction of effective rotational constants Heavy mass  Larger reduction of rotational constants B(o-D 2 ) < B(p-H 2 ) Mass effect of Matrices Rotational constants; B in p-H 2 in o-D 2 ~90%

9. Spectra of I Atom Isolated I atom I... CD 3 complex 2 P 1/2  2 P 3/2 magnetic dipole transition in p-H 2 in o-D 2 I I Intensity ratio in p-H 2 ~0.67 in o-D 2 ~1.25 [I...CD 3 ]/[I] Larger cage effect in o-D 2 M. Fushitani et al. Chem. Phys. Lett. 356 375 (2002)

10. Frequency Shift and Polarizability of Matrices Frequency shift vs. polarizability of matrices Frequency shift; o-D 2 > p-H 2 p-H 2 o-D 2 GasXe, Krp-H 2, o-D 2 2 P 1/2 2 P 3/2

11. Electron-roton Coupling Simultaneous transition magnetic dipole transition (I atom) pure rotational transition (H 2, D 2 ) Frequency shift ~ S 0 (0) *electron of I atom *rotation of hydrogen Electron-roton type transition was observed for the first time. in p-H 2 in o-D 2 I+S 0 (0) S 1 (0)+S 0 (0) p-H 2

12. Phonon Wing o-D 2 > p-H 2 Electron-phonon coupling Larger electron-phonon coupling in o-D 2 Electronic transitionphonon wing M. Pettersson and J. Nieminen, Chem. Phys. Lett. 283, 1 (1998) Ar Kr Xe p-H 2 o-D 2 7400 76007800 Weaker electron-phonon coupling in p-H 2 /o-D 2 The phonon wing of the magnetic dipole transition of the I atom Rare gas solids > p-H 2, o-D 2

13. Conclusions 1) The in situ photolysis of CD 3 I and the formation of CD 3 radicals and I atoms in solid o-D 2 were observed. 2) The differences between solid p-H 2 matrix and o-D 2 matrix were observed. Larger linewidth Smaller rotational constants in o-D 2 Larger cage effect Larger frequency shift Larger electron-phonon coupling  Quantitative studies will clarify the nature of quantum solids. 3) The electron-roton type transition was observed for the first time.

14. I; No changeI...Radical; small shift HI CH 3 I CH 2 DI CD 3 I C2D5IC2D5I M. Fushitani et al. Chem. Phys. Lett. 356 375 (2002)