Global phase angle description of generalized two-dimensional correlation spectroscopy: 1. Theory and its simulation for practical use

The concept of a global phase map derived from generalized two-dimensional synchronous and asynchronous correlation spectra is introduced to extract the purely correlational information by intentionally canceling amplitude information. For the practical usage of a global 2D phase map, a filtering method based on the standard deviation spectrum obtained from the time series intensity profiles is proposed to remove the effect of small amplitude noise. A simulation created with the use of three synthesized bands with exponential decay has clearly detected the only difference in the characteristic rate constant of the decay process in the global 2D phase map, although the three bands have different initial values of the peak intensity amplitudes.