Robert F. Drake

Magnetic studies on μ4‐oxo‐hexa‐μ‐chlorotetrakis [(pyridine) ‐ copper (II)]

The magnetic susceptibility of μ4‐oxo‐hexa‐μ‐chlorotetrakis[(pyridine)copper(II)] has been measured in the temperature range 1.7−294°K. The data may be explained on the basis of simple Heisenberg exchange theory with J=7.65 cm−1, g=2.25, and zJ1 (the intercluster exchange parameter)=−4.0 cm−1.

An improved sample drive rod and sample holder for a P.A.R. Foner‐type vibrating sample magnetometer

The lower section of the instrumented sample drive rod and the sample holder of a P.A.R. Foner‐type vibrating sample magnetometer have been redesigned in order to simplify the disassembly of the rod for removal of the gallium arsenide diode sensor or for repair and to reduce by a significant amount the diamagnetic contribution of these components to the moments of powdered paramagnetic samples studied on the magnetometer.

Magnetic studies on tetrasodium tetramminecopper(II) di-catena-di-μ-thiosulfatocuprate(I) monoammoniate

Abstract The magnetic susceptibility of tetrasodium tetramminecopper(II) di-catena-di-μ-thiosulfatocuprate(I) monoammoniate has been measured in the temperature range 1·6 to 294°K. The data obey the Curie-Weiss law yielding μ eff = 1·80 ± 0·02 B.M. There is a slight deviation from the Curie-Weiss law below 2°K which suggests a weak copper(II)-copper(II) interaction. The interaction is confirmed by the EPR spectrum.

Magnetic studies on the nitrate and bromide salts of the cation di-μ-hydroxobis [di( 1, 10-phenanthroline)chromium(III) ]4+

Abstract The magnetic susceptibilities of powdered samples of di-μ-hydroxobis [di(1,10-phenanthroline)chromium(III)](NO 3 ) 2 ·7H 2 O, and the analogous bromide octahydrate salt have been determined in the temperature range 5 to 283 °K. The dimers exhibit antiferromagnetic exchange interactions with the best fits to the Van Vleck expression for exchange coupled S = 3/2 ions including biquadratic exchange yielding, for the nitrate salt, g = 1.98 ± 0.03, 2J = −42.2 ± 0.5 cm − , and J = 0 cm − and for the bromide salt, g = 1.95 ± 0.03,2J = −29.2 ± 0.6 cm −1 , and j = 0.5 ± 0.1 cm −1 .