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Sourabh N
Nov14-10, 10:51 PM
We derived a formula to calculate the dielectric constant for some materials. It works well for gases and some liquids. But, water has a extraordinary dielectric constant of ~80. I tried googling it up but couldn't find any place which explains (mathematically) why it's so big. The professor said he couldn't find anything on the net either.

Any ideas?

P.S. I can get the formula we derived in class tomorrow morning, if needed.

DrDu
Nov15-10, 03:00 AM
I think it is due to the strong hydrogen bridging bonds between the water molecules. These easily adapt to the electric field thus leading to the high dielectric constant.

nasu
Nov15-10, 10:04 AM
We derived a formula to calculate the dielectric constant for some materials. It works well for gases and some liquids. But, water has a extraordinary dielectric constant of ~80. I tried googling it up but couldn't find any place which explains (mathematically) why it's so big. The professor said he couldn't find anything on the net either.

Any ideas?

P.S. I can get the formula we derived in class tomorrow morning, if needed.

Is the derivation taking into account the permanent dipoles of the water molecules? Or it just assumes induced polarization in external field?