Biology Reference
In-Depth Information
Table 2.2 Is classical thermodynamics at a cross-road, just as classical mechanics was about a
century ago?
Classical mechanics
Classical thermodynamics
1. Object of study
Moving objects
Heat
2. Kinematics :
description of the
space and time
coordination of
moving objects or
changes without
regard to causes
Astronomy (describing the
movement of planets
around the sun, etc.)
Conservation of energy
Descriptive chemistry
Entropy production in irreversible
processes
Descriptive physiology
Heat flow from hot to cold
Descriptive pharmacology
(e.g., therapeutic index)
Free energy decrease in
spontaneous chemical reactions
Descriptive molecular
biology
3. Dynamics : study
of the causes of
motions or changes
Universal gravitation
Role of boundary conditions in self-
organizing chemical reaction-
diffusion systems (?)
Mass-induced spacetime
deformation
4. Crisis
Blackbody radiation (i.e.,
the ultraviolet catastrophe)
Self-reproduction
Genetic code
Morphogenesis
Biological evolution
Constructal law a
Gnergons b (?)
5. Resolution
Quantum of action (1900)
Gnergetics c (twenty-first century?)
6. New field
Quantum mechanics
(1900-1925)
a
The new physical law formulated by Bejan (1997; Bejan and Lorente 2010) who claims that “For
a finite-size system to persist in time (to live), it must evolve in such a way that it provides easier
access to the imposed (global) currents that flow through it”
b Discrete units (-ons) of information (gn-) and energy (-erg-), as exemplified by conformons
(Chap. 8 ). Direct experimental evidence have been obtained in recent years for conformons in
DNA (Sect. 8.3 ) and myosin head (Sect. 8.4 )
c The study of both information (gn-) and energy (-ergy) changes in thermodynamic systems, both
macroscopic and microscopic (Ji 1985a)
2.2 The Franck-Condon Principle (FCP)
2.2.1 FCP and Born-Oppenheimer Approximation
The Franck-Condon Principle originated in molecular spectroscopy in 1925 when
J. Franck proposed (and later Condon provided a theoretical basis for) the idea that,
when molecules absorb photons to undergo an electronic transition from the ground
state (see E 0 in Fig. 2.3 ) to an excited state (E 1 ), the electronic transition occurs so
rapidly that heavy nuclei do not have time to rearrange to their new equilibrium
positions (see q 01 ). In effect, this means that the photon-induced electronic
transitions are most likely to occur from the ground vibrational level (i.e., n 00 ¼
0)
of the ground electronic state to an excited vibrational level (i.e., n 0 ¼
2) of the upper
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