Two-Dimensional Electronic Stark Spectroscopy.

Characterizing ultrafast energy and charge transfer is important for understanding a wide range of systems, from natural photosynthetic complexes to organic photovoltaics. Distinguishing the kinetic processes of energy transfer and charge separation in such systems is challenging due to the lack of clear spectral signatures of charge transfer states, which are typically nonradiative. Stark spectroscopy has proven to be a valuable method for uncovering charge transfer states. Here we extend the dimensionality of Stark spectroscopy to perform two-dimensional electronic Stark spectroscopy. We demonstrate the method on TIPS-pentacene in 3-methylpentane at 77 K. The additional frequency dimension of two-dimensional Stark spectroscopy promises to enable the identification of charge transfer states, their coupling to other charge transfer and exciton states, and their involvement in charge separation processes.

[1]  Guglielmo Lanzani,et al.  Pump‐Probe Spectroscopy in Organic Semiconductors: Monitoring Fundamental Processes of Relevance in Optoelectronics , 2011, Advanced materials.

[2]  G. Lanzani,et al.  Photoinduced transient stark spectroscopy in organic semiconductors: a method for charge mobility determination in the picosecond regime. , 2006, Physical review letters.

[3]  Graham R. Fleming,et al.  Two-dimensional spectroscopy of electronic couplings in photosynthesis , 2005, Nature.

[4]  S. Boxer,et al.  Stark spectroscopy: applications in chemistry, biology, and materials science. , 1997, Annual review of physical chemistry.

[5]  Nicolaas Bloembergen,et al.  Nonlinear Optics , 1977 .

[6]  Kurz,et al.  Ultrafast field-induced dissociation of excitons in conjugated polymers. , 1994, Physical review letters.

[7]  S. Mukamel,et al.  Tight-binding model of the photosystem II reaction center: application to two-dimensional electronic spectroscopy , 2013 .

[8]  David Beljonne,et al.  Singlet exciton fission in solution. , 2013, Nature chemistry.

[9]  Shen,et al.  Photoconductivity in trans-polyacetylene: Transport and recombination of photogenerated charged excitations. , 1988, Physical review. B, Condensed matter.

[10]  Jeffrey A. Squier,et al.  Grism-pair stretcher–compressor system for simultaneous second- and third-order dispersion compensation in chirped-pulse amplification , 1997 .

[11]  Jennifer P Ogilvie,et al.  Pulse shaping based two-dimensional electronic spectroscopy in a background free geometry. , 2014, Optics express.

[12]  Guglielmo Lanzani,et al.  Direct Observation of Ultrafast Field-Induced Charge Generation in Ladder-Type Poly(Para-Phenylene) , 1998 .

[13]  Andrew J. Musser,et al.  Evidence for conical intersection dynamics mediating ultrafast singlet exciton fission , 2015, Nature Physics.

[14]  S. Andrews,et al.  A liquid nitrogen immersion cryostat for optical measurements , 2000 .

[15]  S. Boxer,et al.  Dielectric Asymmetry in the Photosynthetic Reaction Center , 1994, Science.

[16]  Structure and dynamics of pentacene on SiO2: From monolayer to bulk structure , 2012 .

[17]  S. Boxer,et al.  Stark realities. , 2009, The journal of physical chemistry. B.

[18]  B. Diner,et al.  Mixed exciton-charge-transfer states in photosystem II: Stark spectroscopy on site-directed mutants. , 2012, Biophysical journal.

[19]  Alex W Chin,et al.  Real-time observation of multiexcitonic states in ultrafast singlet fission using coherent 2D electronic spectroscopy. , 2016, Nature chemistry.

[20]  H. Matsui,et al.  Field-modulation spectroscopy of pentacene thin films using field-effect devices: Reconsideration of the excitonic structure , 2010 .

[21]  Sadhan Basu,et al.  Theory of Solvent Effects on Molecular Electronic Spectra , 1964 .

[22]  H. Bässler,et al.  Charge transfer transitions in solid tetracene and pentacene studied by electroabsorption , 1981 .

[23]  N. Bloembergen.  Nonlinear Optics (4th Edition) , 1996 .

[24]  V. Shuvalov,et al.  Electric field effects on the chlorophylls, pheophytins, and beta-carotenes in the reaction center of photosystem II. , 2003, Biochemistry.

[25]  D. Hertel,et al.  Ultrafast dynamics of carrier mobility in a conjugated polymer probed at molecular and microscopic length scales. , 2009, Physical review letters.

[26]  R. Miller,et al.  Ultrafast heterodyne-detected transient-grating spectroscopy using diffractive optics , 1998 .

[27]  D. Lockhart,et al.  Electric field effects on the initial electron-transfer kinetics in bacterial photosynthetic reaction centers , 1990 .

[28]  Jennifer P Ogilvie,et al.  Probing Photosynthetic Energy and Charge Transfer with Two-Dimensional Electronic Spectroscopy. , 2012, The journal of physical chemistry letters.

[29]  E. Riedle,et al.  Sub-20-fs pulses tunable across the visible from a blue-pumped single-pass noncollinear parametric converter. , 1997, Optics letters.

[30]  J. Ogilvie,et al.  Chapter 5 Multidimensional Electronic and Vibrational Spectroscopy: An Ultrafast Probe of Molecular Relaxation and Reaction Dynamics , 2009 .

[31]  D. Jonas.  Two-dimensional femtosecond spectroscopy. , 2003, Annual review of physical chemistry.

[32]  E. Venuti,et al.  Intramolecular and Low-Frequency Intermolecular Vibrations of Pentacene Polymorphs as a Function of Temperature , 2004 .