Hall Mobility of Holes in Anthracene

The Hall effect for holes has been measured in high-purity single crystals of anthracene. The magnetic field was directed along each of the $a$, $b$, and $c^{\prime }$ crystallographic directions, and the electric field was in each of the two directions orthogonal to the magnetic field. The Hall mobilities ${\mu }_H$ were computed from the measurements and the drift mobilities ${\mu }_D$ were measured in the same crystals. The ratios $\frac{{\mu }_H}{{\mu }_D}$ are $B_a{I}_b$, -4.3; $B_a{I}_{c^{\prime }}$, -4.8; $B_b{I}_a$, +7.6; $B_b{I}_{c^{\prime }}$, +8.8; $B_{c^{\prime }}{I}_a$, -1.5; and $B_{c^{\prime }}{I}_b$, -1.5. These results are consistent with a band model for charge-carrier transport.