Abstract
In the past, investigation of the semiconductor properties concentrated mainly on the conductivity of unreduced manganese dioxide. Now semiconductor properties have been investigated on samples of different degrees of reduction resulting from homogeneous phase stepwise reduction of 
by the hydrazine method. In the range of 
; from 2 to 1.6, all 
samples exhibited n‐type semiconductor properties. Other properties investigated were dc conductivity, Seebeck coefficient, and electron mobility. A correlation between semiconductor properties and electrochemical properties was developed.