Bond orientational correlations packing

Figure 61. Sixfold bond orientational correlation function for dense random packings of hard disks.

Looking at the structures of alkanes in the figure we can see that while the molecules with an odd number of carbon atoms appear symmetrical (both terminal carbon-carbon bonds being oriented upwards - black lines), where the structures with an even number are asymmetrical in the sense that the terminal carbon-carbon bonds are oriented upwards on the left end of the chain, but downwards on the right end (blue lines). Although the correct explanation is not simple, this example demonstrates how macroscopic properties correlate with microscopic structures. We can assume that odd molecules in the condensed state shall be packed differently from even molecules. 

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