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We investigate ground-state properties of two correlated-hopping electron models, the Hirsch and the Bariev model. Both models are of recent interest in the context of hole superconductivity. Applying the Lanczos technique to small clusters, we numerically determine the binding energy, the spin gaps, correlation functions, and other properties for various values of the bond-charge interaction parameter. Our results for small systems indicate that pairing is favoured in a certain parameter range. However, in contrast to the Bariev model, superconducting correlations are suppressed in the Hirsch model, for a bond-charge repulsion larger than a critical value., Comment: 7 pages (LaTeX) + 6 postcript figures in a separate uuencoded file

We investigate ground-state properties of a one-dimensional correlated hopping electron model in the presence of an external magnetic field which is solvable by Bethe ansatz. We present a general method of calculating magnetization, susceptibility, and chemical potential in exactly solvable spin-1/2 fermion models by deriving a parametric representation of these functions and the magnetic field in terms of the charge and spin distributions, the dressed charge matrix, and the dressed energy at the Fermi points in parameter space. For the correlated hopping model, we numerically calculate the dressed properties-which are given by sets of coupled integral equations-for general values of the field, the band filling, and the interaction parameter. In the special limits of magnetic saturation or large interaction parameter the results are presented in analytic form.