Abstract
The generalised orbital magnetic susceptibility chi (q) given by Hebborn and March (1976) is numerically calculated at small wave vectors q in order to estimate the uniform orbital magnetic susceptibility chi orb given by Hebborn and Sondheimer (1960) from the extrapolation of chi (q) to q=0. For BCC 3d series transition metals the dependence on the electron per atom ratio of chi orb is obtained in the rigid band assumption. The energy band structure and the wavefunctions required in the calculation are obtained in the APW method from the crystal potential of chromium. It is found that chi orb is positive in the middle of the series, shows a large peak at vanadium and becomes negative only near the ends of the series. The calculated values of chi orb for vanadium and chromium are 195 and 106*10-6 EMU/mol, respectively, which are in good agreement with the recent experimental results. Numerical results for the behaviour of chi (q) at small q are also shown.