Effect of H_2O on dielectric properties of berlinite. I. Dielectric constant
Abstract
The dielectric constants of a series of hydrothermally grown berlinite crystals containing increasing amounts of H2O were determined using a two-terminal method and empirically determined edge corrections with k^(T)_(11) ranging from 4.67 to 4.86 and k^(T)_(33) from 4.54 to 4.76. The extrapolated values for 'dry' berlinite are k^(S)_(11)= k^(S)_(33)=4.55. Infrared studies of these crystals show bands at 4400 and 5200 cm^-1 which are attributed respectively to hydroxyl ions and macroscopic and microscopic inclusions of the 6-7 M HCl/H_(3)PO_4 growth medium. The hydroxyl ions are believed to result from terminal P-OH groups at the surfaces of inclusions or as (4H)_Al or (3H)_Al hydroxyl nests. The OH- groups have a negligible influence on the dielectric constant, whereas the inclusions are responsible for the increase in k^(S)_(11) and k^(T)_(33) to 4.8 over the dry value of 4.55.
Additional Information
© 1993 IOP Publishing Ltd. Received 25 February 1992; in final form 3 September 1992. We thank E Philippot, RA Laudise and S Mroczkowski for providing several of the AIPO_4 crystals, R W Shiffer for sample preparation, R A Oswald for capacitance measurements, M Van Kavelaar for scanning electron micrographs and J L Boley for assistance with the infrared acquisition. This work was supported in part by NSF grants EAR-8618200 and EAR-8916064.Additional details
- Eprint ID
- 44007
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- CaltechAUTHORS:20140226-093948188
- EAR-8618200
- NSF
- EAR-8916064
- NSF
- Created
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2014-02-26Created from EPrint's datestamp field
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2022-07-12Created from EPrint's last_modified field
- Caltech groups
- Division of Geological and Planetary Sciences