Two-Dimensional Infrared Spectroscopy

Two-dimensional infrared spectroscopy (2DIR) is a nonlinear infrared spectroscopy technique investigating vibrational modes in condensed-phase systems. The technique provides information beyond linear spectra by spreading the vibrational information along multiple axes, which yields a frequency correlation spectrum with information on vibrational mode coupling, as well as chemical and molecular dynamics with femtosecond resolution.

According to Gelžinis et al., the key strengths of 2D spectroscopy are the following. First, the uncoupling of time and excitation frequency resolution allows the researchers to follow specific states’ dynamics with selective excitation and excellent time resolution. Second, the lack of background signals means that an excellent signal-to-noise ratio can be achieved. Third, a single run of 2D spectroscopy provides information with a wide range of excitation frequencies while using the pump-probe technique that requires many separate measurements. All things considered, for the last fifteen years, 2D spectroscopy has contributed heavily to our understanding of excitation dynamics in photosynthetic molecular complexes. It is a safe bet that it will continue to do so for the foreseeable future.

2DIR experiments have become possible with the development of ultrafast lasers, such as PHAROS and CARBIDE, and the ability to generate femtosecond infrared pulses, e.g., using ORPHEUS-MIR broad bandwidth mid-IR source.

Two-dimensional spectroscopy may be also used in the VIS spectral range, where electronic states are investigated; see two-dimensional electronic spectroscopy (2DES).

  • 100 fs – 20 ps tunable pulse duration
  • 4 mJ maximum pulse energy
  • 20 W maximum output power
  • Single-shot – 1 MHz repetition rate
  • BiBurst
  • Automated harmonic generators (up to 5th harmonic)
  • 190 fs – 20 ps tunable pulse duration
  • 2 mJ maximum pulse energy
  • 80 W maximum output power
  • Single-shot – 2 MHz repetition rate
  • BiBurst
  • Air-cooled version
  • Up to 800 cm-1 spectral bandwidth
  • 2500 – 15 000 nm tuning range
  • < 100 fs pulse duration
  • Up to 400 kHz repetition rate
  • CEP-stable option
  • High conversion efficiency in MIR
  • 1350 – 16000 nm tuning range
  • Single-shot – 2 MHz repetition rate
  • Up to 80 W pump power
  • Up to 2 mJ pump pulse energy
  • 190 – 16000 nm tuning range
  • Single-shot – 2 MHz repetition rate
  • Up to 80 W pump power
  • Up to 2 mJ pump pulse energy
  • Completely automated

An ultrafast vibrational study of dynamical heterogeneity in the protic ionic liquid ethyl-ammonium nitrate. I. Room temperature dynamics

C. A. Johnson, A. W. Parker, P. M. Donaldson, and S. Garrett‑Roe, The Journal of Chemical Physics 13 (154), 134502 (2021).

Hydrogen Bond Exchange and Ca2+Binding of AqueousN-Methylacetamide Revealed by 2DIR Spectroscopy

O. M. Cracchiolo, D. K. Geremia, S. A. Corcelli, and A. L. Serrano, The Journal of Physical Chemistry B 32 (124), 6947-6954 (2020).

Shot-to-shot 2D IR spectroscopy at 100 kHz using a Yb laser and custom-designed electronics

K. M. Farrell, J. S. Ostrander, A. C. Jones, B. R. Yakami, S. S. Dicke, C. T. Middleton, P. Hamm, and M. T. Zanni, Optics Express 22 (28), 33584 (2020).

A 100 kHz Pulse Shaping 2D-IR Spectrometer Based on Dual Yb:KGW Amplifiers

P. M. Donaldson, G. M. Greetham, D. J. Shaw, A. W. Parker, and M. Towrie, The Journal of Physical Chemistry A 3 (122), 780-787 (2018).

Temperature-Induced Collapse of Elastin-like Peptides Studied by 2DIR Spectroscopy

O. Selig, A. V. Cunha, M. B. van Eldijk, J. C. M. van Hest, T. L. C. Jansen, H. J. Bakker, and Y. L. A. Rezus, The Journal of Physical Chemistry B 34 (122), 8243-8254 (2018).

Interplay of Ion–Water and Water–Water Interactions within the Hydration Shells of Nitrate and Carbonate Directly Probed with 2D IR Spectroscopy

J. A. Fournier, W. Carpenter, L. D. Marco, and A. Tokmakoff, Journal of the American Chemical Society 30 (138), 9634-9645 (2016).