1. Adam J. Fleisher Justin W. Young David W. Pratt Department of Chemistry University of Pittsburgh Internal dynamics of water attached to a photoacidic substrate: High resolution electronic spectroscopy of β-naphthol-water in the gas phase. TA-03

2. Solvent in Motion Rotationally resolved electronic spectroscopy – A tunneling splitting provides a measure of the barrier to internal rotation. – This splitting is a function of both the S 0 and S 1 barriers. S0S0 S1S1 torsional coordinate cm -1 torsional coordinate

3. Charge in Motion – MG04 2-naphthol-ammonia2-naphthol-water M.J. Frisch et. al. Gaussian 03 (Gaussian, Inc., Wallingford, CT, 2004).

4. Dynamic charge distribution Start Transition State

5. CW Tunable UV Laser Argon Ion Laser (7 W) Ring Dye Laser (85 mW) Frequency Doubler Reference Station I 2 tube Tunable UV laser beam (300 µW) Monochromator Interferometer

6. Molecular Beam Machine W. A. Majewski, J. F. Pfanstiel, D. F. Plusquellic, and D. W. Pratt, in Laser Techniques in Chemistry, edited by A. B. Myers and T. Rizzo (Wiley, New York, 1995), 101.

7. Rotationally Resolved Data 30531.330533.4Wavenumbers

8. Full Resolution B A Sim Exp 2150 MHz

9. Inertial Parameters A (σ = 0)B (σ = 1) S0S0 A eff (MHz)1725.9(1)1724.9(1) B eff (MHz)548.1(1) C eff (MHz)416.6(1)416.8(1) ΔI eff (amu Å 2 )-1.781-2.609 S1S1 A eff (MHz)1687.4(1)1686.3(1) B eff (MHz)553.4(1)553.3(1) C eff (MHz)417.3(1)417.5(1) ΔI eff (amu Å 2 )-1.741-2.648 Origin (MHz)915333681(30)915339355(30) # lines141458 OMC (MHz)4.15.0 L/G LW (MHz)9/25 Rel. Intensity13 a M.J. Frisch et. al. Gaussian 03 (Gaussian, Inc., Wallingford, CT, 2004). a b

10. Origin of Splitting Energy S0S0 S1S1 A (1) B (3) Qualitative Experimental Conclusions: V 2 in S 0 is greater than V 2 in S 1 The two hydrogen atoms of water must exchange with a 180° movement along the torsional coordinate Quantitative Measures: V 2 in each state is determined assuming a rotation about the b-axis of water Higher order terms (V 4, V 8 ) can be estimated with the aid of ab initio internal rotation pathways A-B energy level splitting in both S 0 and S 1 can be determined

11. Barrier Heights (I) Calculation of W (2) from available data tables determines V 2 in each electronic state. a S0S0 S1S1 ΔA vσ = A 01 – A 00 (MHz)1.01.1 ΔB vσ (MHz)0.1 ΔC vσ (MHz)-0.2 tunneling splitting5673 MHz (0.189 cm -1 ) a D.R. Herschbach. J. Chem. Phys. 31, 91 (1959).

12. Barrier Heights (II) a b Tunneling Splitting as a Function of α'

13. Barrier Heights (III) 2-naphthol-waterphenol-water a S0S0 S1S1 S0S0 S1S1 θ Ra (°)14.5 b 29.299 F (GHz)437.0436.8435 V 2 (cm -1 )206182180130 ΔE(GHz) c 14192043 a G. Berden, W.L. Meerts, M. Schmitt, K. Kleinermanns, J. Chem. Phys. 104, 972, (1996). b from M05-2X/6-31+G* optimization c W.H. Flygare, Molecular Structure and Dynamics. (Prentice-Hall, Inc., Englewood Cliffs, NJ, 1978).

14. Summary Rotationally resolved electronic spectra of the 2-naphthol-water complex revealed internal motion. The results presented are a prerequisite for studying the cluster dipole moment, and therefore the solvent induced charge motion in each electronic state (MG-04). The complicated internal motion of water makes the decomposition of solvation interactions theoretically challenging (MG-04).

15. Philip Morgan Diane Miller Marquette University Ryan Bird Jessica Thomas Casey Clements Patrick Walsh Dr. David W. Pratt University of Pittsburgh Dr. David Plusquellic JB95 development Acknowledgments (I)

17. Hamiltonian and Optics

18. Inertial Parameters A (σ = 0)B (σ = 1) S0S0 A eff (MHz)1725.9(1)1724.9(1) B eff (MHz)548.1(1) C eff (MHz)416.6(1)416.8(1) ΔI eff (amu Å 2 )-1.781-2.609 S1S1 A eff (MHz)1687.4(1)1686.3(1) B eff (MHz)553.4(1)553.3(1) C eff (MHz)417.3(1)417.5(1) ΔI eff (amu Å 2 )-1.741-2.648 Origin (MHz)915333681(30)915339355(30) # lines141458 OMC (MHz)4.15.0 L/G LW (MHz)9/25 Rel. Intensity13 Average Structural Constants Theoretical Constants a (6-31+G*) S0S0 M05-2X A (MHz)1725.41738.5 B (MHz)548.1554.1 C (MHz)416.7421.0 ΔI (amu Å 2 )-2.19-2.34 S1S1 CIS A (MHz)1686.91692.5 B (MHz)553.4551.8 C (MHz)417.4416.9 ΔI (amu Å 2 )-2.18-2.24 a M.J. Frisch et. al. Gaussian 03 (Gaussian, Inc., Wallingford, CT, 2004).

19. Barrier Heights (III) 2-naphthol-waterphenol-water a S0S0 S1S1 S0S0 S1S1 θ Ra (°)14.5 b 29.299 F (GHz)437.0436.8435 V 2 (cm -1 )206182180130 ΔE(GHz) c 14192043 a G. Berden, W.L. Meerts, M. Schmitt, K. Kleinermanns, J. Chem. Phys. 104, 972, (1996). b from M05-2X/6-31+G* optimization c W.H. Flygare, Molecular Structure and Dynamics. (Prentice-Hall, Inc., Englewood Cliffs, NJ, 1978). S0S0 HF / 6-31+G*Percent of V 2 Modified Exp. V 2 (cm -1 )238---206 V 4 (cm -1 )-28-12-24 V 8 (cm -1 )62.55 ΔE(GHz) c 11---16