Chapter 4
Toward More Sophisticated Problems
Abstract In this chapter, examples of actual applications of theoretical chemistry
toward several selected fields in chemistry are to be introduced. The fields dealt
with here cover nanoscience, electrochemistry, catalytic chemistry, and theoretical
biology. It will be hopefully understood that theoretical chemistry is readily useful in
that it can afford us an interpretation of specific but interesting chemical phenomena,
analyses of complicated chemical behaviors, and substantial molecular designs.
Keywords Application · Nanoscience · Electrochemistry · Catalytic chemistry ·
Theoretical biology
4.1 Nanoscience
It is rather recent that nanoscience became one of the foci of practical molecular
science. In this field, molecular properties are attempted to directly connect to characteristics of nanoscale devices, and those properties are most effectively examined
by theoretical chemistry at the molecular level. However, it should be noted that
the essential methodology toward the theoretical analysis of nanoscience is still in
progress. For instance, the interaction mode of cores of a nanoscale device with the
environment such as the external electrodes has not yet been fully understood. In this
section, a couple of examples on these subjects are to be given from the viewpoints
of theoretical chemistry.
4.1.1 Connection of Molecular Wire to the External
Electrode
Most of the molecular electronic devices necessitate the electric connection between
the external electrodes and the core molecule of the device. This is possibly realized
by injection and/or ejection of electrons through appropriate molecular wire provided
with the anchor atoms, for which, e.g., –SH or –SiH group is used to form –S–Au or
–Si–Au bond to the Au electrode as illustrated in Fig. 4.1. A (space) –C–Si anchor
© Springer Nature Singapore Pte Ltd. 2020
K. Tanaka, Theoretical Chemistry for Experimental Chemists,
https://doi.org/10.1007/978-981-15-7195-4_4
155
Toward More Sophisticated Problems
Abstract In this chapter, examples of actual applications of theoretical chemistry
toward several selected fields in chemistry are to be introduced. The fields dealt
with here cover nanoscience, electrochemistry, catalytic chemistry, and theoretical
biology. It will be hopefully understood that theoretical chemistry is readily useful in
that it can afford us an interpretation of specific but interesting chemical phenomena,
analyses of complicated chemical behaviors, and substantial molecular designs.
Keywords Application · Nanoscience · Electrochemistry · Catalytic chemistry ·
Theoretical biology
4.1 Nanoscience
It is rather recent that nanoscience became one of the foci of practical molecular
science. In this field, molecular properties are attempted to directly connect to characteristics of nanoscale devices, and those properties are most effectively examined
by theoretical chemistry at the molecular level. However, it should be noted that
the essential methodology toward the theoretical analysis of nanoscience is still in
progress. For instance, the interaction mode of cores of a nanoscale device with the
environment such as the external electrodes has not yet been fully understood. In this
section, a couple of examples on these subjects are to be given from the viewpoints
of theoretical chemistry.
4.1.1 Connection of Molecular Wire to the External
Electrode
Most of the molecular electronic devices necessitate the electric connection between
the external electrodes and the core molecule of the device. This is possibly realized
by injection and/or ejection of electrons through appropriate molecular wire provided
with the anchor atoms, for which, e.g., –SH or –SiH group is used to form –S–Au or
–Si–Au bond to the Au electrode as illustrated in Fig. 4.1. A (space) –C–Si anchor
© Springer Nature Singapore Pte Ltd. 2020
K. Tanaka, Theoretical Chemistry for Experimental Chemists,
https://doi.org/10.1007/978-981-15-7195-4_4
155