A quantitative model of the cislunar magnetospheric field is developed, incorporating the following field sources: (i) the geodipole, (ii) the ring-current/plasma-sheet system modelled by a smooth current surface, and (iii) the magnetopause current system including the return current of the magnetotail sheet. The shape of the intra-magnetospheric current layer depends on the geodipole tilt, in line with experimental findings by Russell and Brody (1967) and Bowling(1974). The current density profile versus geocentric distance in the layer is matched in accordance with existing magnetic measurements (Sugiura, 1972; Behannon, 1968). The magnetopause current is computed from the requirement of zero total field outside the cavity, the latter's shape being assumed as given by an analytic expression fitting the experimental data (Fairfield, 1971).
Force line configurations are computed for the quiet-state model with dipole tilt angles 0, 10, 20 and 30 degrees. A study of the conjugate point shift in the latter case has shown that latitudinal shift reaches ~2 degrees in the midnight high-latitude zone, the longitudinal displacement being of the order of 10 degrees in the predawn/premidnight sectors. A disturbed-state magnetospheric configurations are simulated for two typical stages of a geomagnetic storm, including the formation of the neutral line in the near tail region.