title: Accurate determination of complex χ(2) spectrum of the air/water interface.
abstract: Discussion on the structure of the water surface relies on accurate determination of the χ(2) spectrum. For obtaining accurate χ(2) spectrum of the air/water interface in the OH stretch region, we performed heterodyne-detected vibrational sum-frequency generation measurements with a high phase accuracy, and also examined the validity of the phase and amplitude calibration using different non-resonant materials. In contrast to the previous reports, it was concluded that the imaginary part of the χ(2) spectrum of the air/water interface does not exhibit noticeable positive resonance in the low frequency region within the experimental error. This result urges us to reconsider the structure of the air/water interface based on the accurate χ(2) spectrum.
authors.affiliation: Molecular Spectroscopy Laboratory, RIKEN, 2-1 Hirosawa, Wako, Saitama 351-0198, Japan.
authors.forename: Satoshi
authors.initials: S
authors.lastname: Nihonyanagi
authors.affiliation: Molecular Spectroscopy Laboratory, RIKEN, 2-1 Hirosawa, Wako, Saitama 351-0198, Japan.
authors.forename: Ryoji
authors.initials: R
authors.lastname: Kusaka
authors.affiliation: Molecular Spectroscopy Laboratory, RIKEN, 2-1 Hirosawa, Wako, Saitama 351-0198, Japan.
authors.forename: Ken-ichi
authors.initials: K
authors.lastname: Inoue
authors.affiliation: Molecular Spectroscopy Laboratory, RIKEN, 2-1 Hirosawa, Wako, Saitama 351-0198, Japan.
authors.forename: Aniruddha
authors.initials: A
authors.lastname: Adhikari
authors.affiliation: Molecular Spectroscopy Laboratory, RIKEN, 2-1 Hirosawa, Wako, Saitama 351-0198, Japan.
authors.forename: Shoichi
authors.initials: S
authors.lastname: Yamaguchi
authors.affiliation: Molecular Spectroscopy Laboratory, RIKEN, 2-1 Hirosawa, Wako, Saitama 351-0198, Japan.
authors.forename: Tahei
authors.initials: T
authors.lastname: Tahara