  We study theoretically the quantum size effects in a one-dimensional
semimetal by a Boltzmann transport equation. We derive analytic expressions for
the electrical conductivity, Hall coefficient, magnetoresistance, and the
thermoelectric power in a nanowire. The transport coefficients of semimetal
oscillate as the size of the sample shrinks. Below a certain size the semimetal
evolves into a semiconductor. The semimetal-semiconductor transition is
discussed quantitatively. The results should make a theoretical ground for
better understanding of transport phenomena in low-dimensional semimetals. They
can also provide useful information while studying low-dimensional
semiconductors in general.
