Chapter 11
Summary
Abstract The present chapter summarizes the outline of the theory of SFG
spectroscopy described in this book, including the fundamental and detailed theory
of χ (2) and application of computational SFG analysis for realistic interfaces.
This chapter also shows future directions of the SFG spectroscopy, which will be
greatly facilitated in collaboration of experimental advances and the computational
analysis. Theoretical interpretation with the aid of reliable computation will be
increasingly important in the future of the surface nonlinear spectroscopy.
Keywords Fundamental theory of χ (2) · Modeling of polarization · Future
directions
In this book, fundamental theory of the surface nonlinear spectroscopy and related
principles are presented. The principal aim is toward comprehensive understanding
of the vibrational SFG spectroscopy through close collaboration of experimental
measurement and theoretical analysis. Here we briefly summarize the outline of the
theory described in this book.
11.1 Outline of Theory
The theory of SFG consists of both macroscopic and microscopic aspects of the
surface nonlinear spectroscopy, which were treated in Chaps. 2 and 3, respectively.
The macroscopic aspect in Chap. 2 deals with the electromagnetic processes in
which the nonlinear polarization is induced at the interface and thereby emits the
radiation of sum frequency. On the other hand, the microscopic aspect in Chap. 3
defines material properties of the interface related to the nonlinear response.
Furthermore, Chap. 4 provides the microscopic formulations of the frequencydependent nonlinear susceptibility of the interface χ (2) ((, ω 1 , ω 2 ) by two routes, on
the basis of the energy representation and the time-dependent representation. These
two routes of formulations allow for calculating χ (2) ((, ω 1 , ω 2 ) by molecular
© Springer Nature Singapore Pte Ltd. 2018
A. Morita, Theory of Sum Frequency Generation Spectroscopy,
Lecture Notes in Chemistry 97, https://doi.org/10.1007/978-981-13-1607-4_11
261
Summary
Abstract The present chapter summarizes the outline of the theory of SFG
spectroscopy described in this book, including the fundamental and detailed theory
of χ (2) and application of computational SFG analysis for realistic interfaces.
This chapter also shows future directions of the SFG spectroscopy, which will be
greatly facilitated in collaboration of experimental advances and the computational
analysis. Theoretical interpretation with the aid of reliable computation will be
increasingly important in the future of the surface nonlinear spectroscopy.
Keywords Fundamental theory of χ (2) · Modeling of polarization · Future
directions
In this book, fundamental theory of the surface nonlinear spectroscopy and related
principles are presented. The principal aim is toward comprehensive understanding
of the vibrational SFG spectroscopy through close collaboration of experimental
measurement and theoretical analysis. Here we briefly summarize the outline of the
theory described in this book.
11.1 Outline of Theory
The theory of SFG consists of both macroscopic and microscopic aspects of the
surface nonlinear spectroscopy, which were treated in Chaps. 2 and 3, respectively.
The macroscopic aspect in Chap. 2 deals with the electromagnetic processes in
which the nonlinear polarization is induced at the interface and thereby emits the
radiation of sum frequency. On the other hand, the microscopic aspect in Chap. 3
defines material properties of the interface related to the nonlinear response.
Furthermore, Chap. 4 provides the microscopic formulations of the frequencydependent nonlinear susceptibility of the interface χ (2) ((, ω 1 , ω 2 ) by two routes, on
the basis of the energy representation and the time-dependent representation. These
two routes of formulations allow for calculating χ (2) ((, ω 1 , ω 2 ) by molecular
© Springer Nature Singapore Pte Ltd. 2018
A. Morita, Theory of Sum Frequency Generation Spectroscopy,
Lecture Notes in Chemistry 97, https://doi.org/10.1007/978-981-13-1607-4_11
261