Development of a femtosecond diffuse reflectance spectroscopic system, evaluation of its temporal resolution, and applications to organic powder systems

An ultrafast time-resolved diffuse reflectance spectroscopic system has been developed as a potential instrument for analyzing photophysical and photochemical dynamics of light scattering materials such as powder and opaque suspension, using an amplified femtosecond Ti:sapphire laser as a light source. Transient absorption spectra of organic powder, covering the wavelength region from 400 to 760 nm, were precisely obtained by using a stable and bright femtosecond white-light continuum as a probe light. An ultrashort light pulse is temporally broadened owing to numerous times of refraction, reflection, and diffraction in scattering materials. This affects the temporal resolution of transient absorption measurements, which was examined and discussed in detail by using a simple numerical model with time-dependent light propagation of a short pulse. From the simulation and experimental results, it was shown that the temporal resolution of transient absorption measurement is less than a few ps under a certain measurement condition, although it strongly depends on the optical properties of the sample; scattering and absorption coefficients. Some applications to the analysis of excited dynamics of organic molecules in polymer latex and molecular microcrystalline powder are also demonstrated.

[1]  S. Razin,et al.  Ion charge state distribution in plasma of electron cyclotron resonance discharge sustained by powerful millimeter wave radiation , 1998 .

[2]  G. D. Mills,et al.  Design aspects of a compact, single-frequency, permanent-magnet electron cyclotron resonance ion source with a large uniformly distributed resonant plasma volume , 1998 .

[3]  R. Schmieder,et al.  Experimental results from the Brookhaven National Laboratory test electron beam ion source , 1998 .

[4]  S. Gammino,et al.  Preliminary results of the 14 GHz SERSE superconducting electron cyclotron resonance ion source working in high-B mode , 1998 .

[5]  Optical deflection setup for stress measurements in thin films , 1998 .

[6]  O. Kaneko,et al.  HIGH-CURRENT NEGATIVE-ION BEAM ACCELERATION WITH A LARGE NEGATIVE-ION SOURCE FOR LARGE HELICAL DEVICE-NEUTRAL BEAM INJECTION SYSTEM , 1998 .

[7]  B. Heinemann,et al.  Large-area radio frequency plasma sources for fusion applications , 1998 .

[8]  F. Wilkinson,et al.  Electron Transfer Reactions of Anthracene Adsorbed on Silica Gel , 1997 .

[9]  H. Masuhara,et al.  Nanosecond Electron Transfer Dynamics between Traps in Zeolites Studied by Double-Pulse Excitation Diffuse Reflectance Spectroscopy , 1997 .

[10]  H. Koshima,et al.  Electronic Structure and Dynamics of the Excited State in CT Microcrystals As Revealed by Femtosecond Diffuse Reflectance Spectroscopy , 1997 .

[11]  Andrea Colombo,et al.  Does Interfacial Charge Transfer Compete with Charge Carrier Recombination? A Femtosecond Diffuse Reflectance Investigation of TiO2 Nanoparticles , 1996 .

[12]  H. Masuhara,et al.  Localization of a charge transfer excited state in molecular crystals: a direct confirmation by femtosecond diffuse reflectance spectroscopy , 1996 .

[13]  S. Hashimoto Diffuse reflectance laser photolytic studies of pyrene included in zeolites Formation of pyrene anion radicals via excited-state electron transfer between guest molecules , 1996 .

[14]  W. Steele,et al.  ROTATIONAL RELAXATION IN FLUID NITROGEN : AN AMBIGUITY IN THE INTERPRETATION OF THE Q-BRANCH COLLAPSE ? , 1996 .

[15]  J. Kochi,et al.  Photoinduced Electron Transfer in Charge-Transfer Crystals by Diffuse-Reflectance (Picosecond) Time-Resolved Spectroscopy , 1995 .

[16]  R. M. Bowman,et al.  Femtosecond diffuse reflectance spectroscopy of TiO2 powders , 1995 .

[17]  H. Hamaguchi,et al.  Vibrational cooling process in solution probed in picosecond time-resolved Raman spectroscopy. Analysis of the cooling kinetics , 1995 .

[18]  I. Lednev,et al.  Photochemistry of Stilbene Adsorbed on Silica Gel and NaX Zeolite. A Diffuse Reflectance Laser Flash Photolysis Study , 1994 .

[19]  H. Masuhara,et al.  A picosecond diffuse reflectance laser photolysis study on phenanthrene—pyromellitic dianhydride charge-transfer crystal , 1994 .

[20]  H. Masuhara,et al.  Picosecond diffuse reflectance laser photolysis study on 9,10-dichloroanthracene and 9,10-dibromoanthracene microcrystals , 1994 .

[21]  Hiroshi Masuhara,et al.  Each dopant can absorb more than ten photons: Transient absorbance measurement at excitation laser wavelength in polymer ablation , 1994 .

[22]  P. Kamat PHOTOCHEMISTRY ON NONREACTIVE AND REACTIVE (SEMICONDUCTOR) SURFACES , 1993 .

[23]  J. K. Thomas Physical aspects of photochemistry and radiation chemistry of molecules adsorbed on silica, .gamma.-alumina, zeolites, and clays , 1993 .

[24]  K. Hamano,et al.  Transient absorption spectroscopic study on photothermal process and laser ablation of poly(N-vinylcarbazole) film , 1993 .

[25]  E Gratton,et al.  Propagation of photon-density waves in strongly scattering media containing an absorbing semi-infinite plane bounded by a straight edge. , 1993, Journal of the Optical Society of America. A, Optics and image science.

[26]  D. Oelkrug,et al.  Absorption and emission spectroscopy in scattering media: modelling of fluorescence decay curves and photometric laws for systems with inhomogeneous absorber distribution , 1992 .

[27]  H. Miyasaka,et al.  Femtosecond laser photolysis studies on the cooling process of chrysene in the vibrationally hot S1 state in solution , 1992 .

[28]  R A Mathies,et al.  The first step in vision: femtosecond isomerization of rhodopsin. , 1991, Science.

[29]  H. Masuhara,et al.  Absorption spectra and dynamics of the triplet state in p-terphenyl powder systems: A diffuse reflectance laser photolysis study. , 1990 .

[30]  M. Fox,et al.  Titanium dioxide photooxidation of thiocyanate: (SCN)2.cntdot.- studied by diffuse reflectance flash photolysis , 1990 .

[31]  N. Mataga,et al.  The bell-shaped energy gap dependence of the charge recombination reaction of geminate radical ion pairs produced by fluorescence quenching reaction in acetonitrile solution , 1988 .

[32]  Tatsuo Yajima,et al.  Ultrafast Phenomena VI , 1988 .

[33]  H. Hiraoka,et al.  Dopant‐induced ablation of polymers by a 308 nm excimer laser , 1988 .

[34]  K. Yoshihara,et al.  Picosecond transient absorption spectral and kinetic study on benzophenone microcrystals by diffuse reflectance laser photolysis method , 1987 .

[35]  D. Oelkrug,et al.  Modelling of transient production and decay following laser excitation of opaque materials , 1987 .

[36]  J. Scaiano,et al.  Intrazeolite photochemistry. IV. Studies of carbonyl photochemistry on the hydrophobic zeolite Silicalite using time-resolved diffuse reflectance techniques , 1986 .

[37]  Graham R. Fleming,et al.  Chemical applications of ultrafast spectroscopy , 1986 .

[38]  F. Wilkinson,et al.  Detection of transient absorption in a dyed cotton fabric and in semiconductor powders by diffuse reflectance laser flash photolysis , 1985 .

[39]  F. Wilkinson,et al.  Detection of triplet—triplet absorption in microcrystalline benzophenone by diffuse-reflectance laser flash photolysis , 1984 .

[40]  R. Kessler,et al.  Transient Decay Following Pulse Excitation of Diffuse Scattering Samples , 1983 .

[41]  H. Miyasaka,et al.  Picosecond Absorption Spectra and Relaxation Processes of the Excited Singlet State of Pyrene in Solution , 1983 .

[42]  R. Kessler,et al.  Diffuse reflectance triplet–triplet absorption spectroscopy of aromatic hydrocarbons chemisorbed on γ-alumina , 1981 .

[43]  A Ishimaru,et al.  Backscattering of a picosecond pulse from densely distributed scatterers. , 1979, Applied optics.

[44]  G. Porter,et al.  Chemical Reactions Produced by Very High Light Intensities , 1949, Nature.