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The level of interaction between the states of the system and its environment
(macro-level)
In this case, it is the dynamics of the macro-level that is responsible for the
apparent properties of the system.
6.3.2 Some Details: Self-Organization, Dissipative
and Conservative, Self-Assembly, Stigmergy, etc.
Let us discuss some concepts that are used along with the notion of “self-organi-
zation” and, in some cases, against it. The most commonly used of them is the
notion of “self-assembly.”
The notion of “self-assembly” has chemical origins. It was introduced in 1987 by
the famous French chemist, Nobel laureate Jean-Marie Lehn, to distinguish, among
the many phenomena of spontaneous self-organization, the processes of spontane-
ous structure formation in systems that are in the state of thermodynamic equilib-
rium. Indeed, we know a large number of such processes of structure formation
under the equilibrium or, more precisely, under close to equilibrium conditions.
Among them, for example, are helix-coil transitions in polymer molecules, the
formation of supramolecular structures of amphiphilic molecules (micelles, lipo-
somes, bilayers), and so on up to crystallization processes. The term “self-assem-
bly” is mainly used in relation to molecular systems. Nevertheless, self-assembly
processes were found in other micrometer structures. Thus, electrochemical pro-
cesses at the border between heptane and a water solution of copper sulfate led to
formation of transparent copper films about 1
m thick on the heptane side and
dendrite-like copper formations on the copper sulfate side.
Nevertheless, while being seemingly reasonable, contrasting the equilibrium and
nonequilibrium processes of spontaneous pattern formation does not appear justi-
fied. First of all, strictly equilibrium processes are rare in practice. It is well known
how technically difficult it is to grow large monocrystals under isothermal condi-
tions, maintaining small growth rates. Chemical processes are usually carried out
under conditions close to equilibrium. A criterion of this proximity is the revers-
ibility of the process—a necessary condition for equilibrium. Understanding this
helps to avoid the uncertainty that arises in some cases, when physical and chemical
mechanisms are identical in terms of their physicochemical mechanisms, but
differing in their complexity. Thus, the formation of supramolecular assemblies
of amphiphilic molecules—for example, micelle formation in solution—undoubt-
edly belongs to self-assembly according to the definition of this term. But at the
same time, lipid bilayers—the basis of cell membranes—can hardly be attributed to
this category. Recently, in order to avoid unnecessary confusion, the phenomenon
of spontaneous structure formation in equilibrium systems is increasingly fre-
quently called conservative self-organization.
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