A one-dimensional lattice of spacing ‘a’ has potential distribution of the type as considered in the Kronig-Penney model. The value of the potential is –V at each lattice point and abruptly changes to zero at a distance of 0.1a on either side of the lattice point. Determine the width of the first energy gap in the electron energy spectrum .

A one-dimensional lattice of spacing ‘a’ has potential distribution of the type as considered in the Kronig-Penney model. The value of the potential is –V at each lattice point and abruptly changes to zero at a distance of 0.1a on either side of the lattice point. Determine the width of the first energy gap in the electron energy spectrum .