BioPHYSICAL chemistry

10.16Optical spectroscopy has shown that the excited state of chlorophyll

can be quenched by the presence of zeaxanthin, forming a transitory

oxidized state of the carotenoid.

10.17The length of the conjugation differs in the two carotenoids, giving

them different energies for the electronic states.

10.18 Tunneling is the process by which a particle makes a transition

between two states through an intermediate state that is classically

forbidden. Tunneling depends upon distance, the size of the energy

barrier, and the energy of the particle.

10.19 Scanning tunneling microscopy is a technique that makes use of

the ability of an electron to tunnel through a vacuum to probe the

surface of an object at an atomic level.

10.20 Atomic force microscopy is a technique that makes use of a can-

tilever to move a probe across a surface to probe the surface at an

atomic level.

10.21 Many answers accepted.

10.22 Since the two acceptors are identical, the free-energy differences

for the reactions should be about equal. However, the slower rate

can be explained by assuming that one acceptor has a much higher

reorganization energy.

10.23 The rate is seen to be nearing a maximal value at the upper range

of the free-energy differences, so the reorganization energy is about

600 meV.

CHAPTER 11

11.1

11.2

11.3

11.4

11.5 μ=.

+

=

×

+

=×

mm

mm

CO m

CO

p

12 16

12 16

114 10−^26 kg

λπ= 2 c

m

k

e

5

2

Z

k

me

1

2

Z

k

me

E

k

m

==

ZZω

22

462 ANSWERS TO PROBLEMS

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