Last Update 24/ 08/ 2000
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Introduction
This frame is directed to the study on two fields: in one option the rotation axis study on tetrahedral and lower symmetry objects like pyramids with triangular base and different components on the corners. The other option enables the absolute configuration study on organic molecules with at least one saturated carbon.
Description of the application in symmetry
The default figure directs the four-fold inversion axis perpendicular to this screen. Depending on the selected object by clicking on the little structures on the right side of the figure the new axis in this orientation may be the two-fold axis. It can be operated by a push and drag mouse action on the green square on the horizontal scrolling bar. On the other hand, by a similar action on the vertical scrolling bar a three-fold axis may be perpendicular to this screen, depending on the symmetry of the selected object.
Suggested symmetry exercise
Verify which of the available structures exhibit the two-fold axis, which the three-fold axis on the orientation mentioned above and which exhibit more than one symmetry axis.
Description of the application in organic chemistry
The absolute configuration of an asymmetric carbon of a chiral organic molecule can be determined with the aid of a framework molecular model. This conclusion is obtained after drawing and imagining the molecule in space, when a molecular model is not available. It requires experience and vision in three dimensions. However, the molecule is not always presented with the appropriate orientation for the direct determination of its absolute configuration.
For example, when the group of lowest priority is directed away from the viewer the determination of the configuration is direct, just having to trace an arrow in the decreasing priority sense of the other groups. If the molecule is presented in any other orientation, it must be rotated until reaching a convenient orientation.
Therefore this application was developed aiming to help the students determine the absolute configuration of either imaginary or real molecules while their spatial vision is being developed.
Suggested organic chemistry exercise
Determine the absolute configuration of bromochlorofluoromethane supposing that the atom of bromine is the red sphere, chlorine green, fluorine blue and hydrogen yellow.
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Table of subjects.