Department of Physics, Kazakh National Technical University
22 Satpaev str., Almaty, 480013, Kazakhstan
In a basis of creation of molecular devices biochips there is the idea of
self-ordering macromolecules with use of a method of the biomolecules self-organization. A
basic element of the molecular device should be the organized molecular ensemble
representing upper-molecular formations, in which the initial molecules are connected among
themselves definitely. Such ensembles form by changing concentration, ??, temperature,
pressure and other parameters of reaction .This ensembles product by self-organization of some
reacting components or the molecular layers by means of consecutive adsorption.
The molecular devices should have functionality to react on the external signals. The
external signals play a role of the starting mechanism bringing in action a lot of the important
processes. For performance of the basic functions the similar systems should have receivers
for absorption of a signal and further use of its energy for conformational changes of molecular
complexes.
The effect of storing in memory molecular structures can be realised using conformational
transformation macrostructure under influence of a electrical field or light. The ensembles of
biomolecules carry out consecutive reactions on the molecular level with the certain
reproducibility and efficiency, that cannot be achieved by means of modern electronic
technology.
On the initially it is perspective of researches modelling functional properties of
biomolecules on the basis of their liquid crystal properties, which are sensitive to external
influences and are controllable.
The research of the power and entropy parameters of processes of self-organization before
made by us has shown a conducting role of the entropy factors in conformational changes
processes [1,2].
Therefore it is necessary to know the conformational changes for controllable management
of the molecular device. The conformational changes are caused by the entropy factors. It is
difficult to find separately the conformational and dehydrated contributions to complete change
of entropy.
For division conformational and dehydrated contributions we have determined complete
entropy of aggregation of hydrocarbon molecules. It was made by representation of system
water hydrocarbon as system of contacts.
dS = R ln g h N
where R - universal gas constant, h - solubility hydrocarbon in water, N - quantity of evaporated water molecules, which experimentally can be find , g - constant.
This entropy change is connected with two effects
1) the conformational changes D Sconf and
2) the aggregation of molecules chlorophyllin during their dehydration,
D
Sdehydr
D S = D Scon + D Sdehydr.
Thus, for the first time we managed to divide conformational and dehydrated
contributions to the entropy change and to show, that the entropy-managed process of
self-ordering of chlorophyllin molecules in water is caused mainly by conformational
transformations of structure of the chlorophyllin water solution [3,4].
We investigate spectral photosensitivity heterosystem of the solution chlorophyllin-silicon
(picture). The broadening of heterojunction spectral photosensitivity to short-wave field is
observed. This effect may be explained by the next factors. 1. Brightening properties of
chlorophyllin because of by the decrease of silicon face reflection coefficient in short-wave field.
2. The recombination centers of silicon face are passivated by active groups of chlorophyllin
molecules. 3. The quazi-zone structure is formed near to silicon face by short-range order of
spatial position of chlorophyllin molecules. The chlorophyllin on silicon face might be taken in
account as broadband gap semiconductor.
The spectral photosensitivity curve doesn't have the kink which characteristic to semiconductor heterojunction with different energy gaps. The heterojunction interface is non-defectives because of ability of the chlorophyllin molecules to repeat the orientation of the silicon matrix atoms.
Literature
email: kt011@hotmail.kz