Question

Iodine is a semiconductor under normal conditions (band gap $\sim$ 1.3eV). However, on compression to about 350 kbar pressure, it becomes conducting. The change is due to

• A. formation of a partially filled band
• B. change in electronic configuration
• C. better overlap of molecular orbitals
• D. high ionization potential

Answer 1

Answer: (A)

formation of a partially filled band

Iodine is a semiconductor under general conditions. However, when compressed on applying pressure, Iodine becomes conducting due to the formation of a partially filled band. The partial electrons help in conducting.