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Starting from a regular, static and spherically symmetric spacetime, we present a stellar model formed by two sources of ordinary and quintessence matter both with anisotropic pressures. The ordinary matter, with density [Formula: see text], is formed by a fluid with a state equation type Chaplygin [Formula: see text] for the radial pressure. And the quintessence matter, with density [Formula: see text], has a state equation [Formula: see text] for the radial pressure and [Formula: see text] for the tangential pressure with [Formula: see text]. The model satisfies the required conditions to be physically acceptable and additionally the solution is potentially stable, i.e. [Formula: see text] according to the cracking concept, and it also satisfies the Harrison–Zeldovich–Novikov criteria. We describe in a graphic manner the behavior of the solution for the case in which the mass is [Formula: see text] and radius [Formula: see text][Formula: see text]km which matches the star EXO 1785-248, from where we obtain the maximum density [Formula: see text] for the values of the parameters [Formula: see text], [Formula: see text].

A charged stellar model is presented by constructing a solution to the Einstein–Maxwell equations system in a spherically symmetrical static time-space. The rate of compactness for the model depends on two parameters [Formula: see text], one of them [Formula: see text] associated to the charge, which allows a value of compactness [Formula: see text] higher than the neutral case. The density and pressure are regular functions, positive and monotonically decreasing and the function of charge is positive regular and monotonically increasing, its shown that the model satisfies the condition of causality, the geometry is regular and as such the model is physically acceptable. Although the model can be applicable for a variety of stars, considering a star with mass [Formula: see text] for [Formula: see text] the range of compactness is [Formula: see text] and radius [Formula: see text], in this case the range of values for the central density is [Formula: see text] greater than the value of the nuclear density and consistent with that expected for stars with this compactness rate.

A stellar model with an electrically charged anisotropic fluid as a source of matter is presented. The radial pressure is described by a Chaplygin state equation, [Formula: see text], while the anisotropy [Formula: see text] is annulled in the center of the star [Formula: see text] is regular and [Formula: see text], the electric field, is also annulled in the center. The density pressures and the tangential speed of sound are regular, while the radial speed of sound is monotonically increasing. The model is physically acceptable and meets the stability criteria of Harrison–Zeldovich–Novikov and in respect of the cracking concept the solution is unstable in the region of the center and potentially stable near the surface. A graphic description is presented for the case of an object with a compactness rate [Formula: see text], mass [Formula: see text] and radius [Formula: see text] km that matches the star Vela X-1. Also, the interval of the central density [Formula: see text], which is consistent with the expected magnitudes for this type of stars, which shows that the behavior is accurate for describing compact objects.