Dear Hailong,

I searched all dielectric constants table however, I did not find any determined value for propylene oxide. However, I found the dielectric constant of Ethylene oxide which is13.

Since both structures are uite similar, you can use the value of 13.

Attached is a list of all measured dielectric constants.

Hoping this will be helpful,

Rafik

Dear Rafik,

             It is a good suggestion, thanks a lot.

According to the following reference (not new, but apparently reliable):

http://deepblue.lib.umich.edu/bitstream/handle/2027.42/6182/bac7088.0001.001.pdf?sequence=5&isAllowed=y

the dielectric constant of propylene oxide is 16.0 , see Table XV on page 65 of the thesis, page 78 in the pdf file.

I has been taken from the classical book of Smyth: Dielectric behavior and structure (1955)