area and volume of a sphere are, respectively
A = πr
2
V =
4
3
πr
3
(1.1)
and applying simple algebra, the ratio of surface area to volume for
the buckyball is over five billion times larger than for the soccer ball. This
massive increase in surface area means that a far larger fraction of a
nanoscale system is able to participate in chemical reactions or physical processes such as charge or energy transfer than a corresponding bulk system and that the system is heavily defined by its surface
CH 3 (CH 2 ) 11 group OH group
~10 nm
~5 nm
Figure 1.3 An assembly of 48 dodecanol molecules forming a hypothetical
aggregate of length 10 nm and width 5 nm. The filled circles represent carbon atoms
and the open circle represents the oxygen of the terminal hydroxyl group of the
molecule. Hydrogen atoms are not shown for convenience. This two-dimensional
assembly is held together by a combination of hydrogen bonds and hydrophobic
interactions (discussed further in Chapters 2 and 3).
THE NANOSCALE DIMENSION
7
A = πr
2
V =
4
3
πr
3
(1.1)
and applying simple algebra, the ratio of surface area to volume for
the buckyball is over five billion times larger than for the soccer ball. This
massive increase in surface area means that a far larger fraction of a
nanoscale system is able to participate in chemical reactions or physical processes such as charge or energy transfer than a corresponding bulk system and that the system is heavily defined by its surface
CH 3 (CH 2 ) 11 group OH group
~10 nm
~5 nm
Figure 1.3 An assembly of 48 dodecanol molecules forming a hypothetical
aggregate of length 10 nm and width 5 nm. The filled circles represent carbon atoms
and the open circle represents the oxygen of the terminal hydroxyl group of the
molecule. Hydrogen atoms are not shown for convenience. This two-dimensional
assembly is held together by a combination of hydrogen bonds and hydrophobic
interactions (discussed further in Chapters 2 and 3).
THE NANOSCALE DIMENSION
7