Let us consider an organic sample of benzene with the molecular formula C6H6. By reducing the size of the benzene (up to nano) is there any change in the molecular formula?
As implied by Alexandre's answer the answer is complex. I'm inclined to say no, but there are multiple cases where you could as well argue the answer is yes. Maybe I try to explain this by follwing your benzene example:
The bond length in benzene is intermediate between the C-C single bond and the C=C double bound approximately 0.140 nm. Therefore you may calculate the size of the benzene ring is below a nm.
Therefore you can safely assume that reducing a cluster of these (obviously not formed at RT) will not change the individual molecular formula of the majority of its components. Nevertheless, depending on the mechanism used to break the macrocluster into smaller pieces, bonds may be broken, therefore you might have a lot more dengling bonds on the surface of your cluster. If you break bonds at the surface of your nanocluster you will experience relaxation, therefore the geometry of your benzene ring will change and its properties change (besides the obvious property change invoked by the cleavage of a bond). If your cluster is small enough, this might ultimately lead to a complete different behavior of your cluster, and may also lead to a different "average" molecular formular, although in the center of your cluster benzene will have the original molecular formular.
Be aware that reducing the size, does at least two things a) increasing surface, thus the properties might be dominated by surface effects rather than bulk properties, b) changes the physical interaction with e.g. electro-magnetic waves, which, in turn, gives rise to unique optical properties.
No and yes. If the energy introduced in the system by the equipment and the environment allows say, for instance, an oxydation of a material, yes, it is possible to change the chemical formula (or chemical compound). But is not that normally happens. This can happen mainly with thermosensible products under very favorable conditions.
Thanks to all,
I have few questions
By the extract of above when reducing the bulk material upto nano size by chemical or some other technique, There is some change in their molecular formula or some bonds are broaken or changes in bond length
my questions are
1) How do they confirm the nano material by Powder XRD by compare with JCPDS (I hope JCPDS is powder XRD of pure single crystal structure)
2) By change in molecular formula PXRD also be different for that material?
3)What is the correct tool to conform the nano material after successful synthesis?
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