Effective Bohr radius of a hydrogenic donor
= Effective Bohr radius of a hydrogenic donor
{title2=$a_B^*$}
In a scalar effective-mass dielectric model, the donor radius is $a_B^*=\epsilon_r(m_e/m^*)a_0$. The <effective mass> reduces the kinetic-energy scale and dielectric screening weakens attraction. The corresponding binding energy scales as $(m^*/m_e)\epsilon_r^{-2}$ times the vacuum hydrogen binding energy.