A large grid of equilibrium models suitable for adiabatic and nonadiabatic seismological investigations of pulsating white dwarfs of the DAV and DBV types is presented. The models are computed with the help of an evolution code which is described in detail. An interpolation code which is used to generate all the variables needed for pulsation studies and to increase, as needed, the number of shells by an interpolation technique is also described. The basic structure of the models is that of a layered configuration consisting of an almost pure carbon core surrounded by an almost pure helium layer (DB stars) itself surrounded by an almost pure hydrogen layer (DA stars). The composition transition zones are treated under the assumption of diffusive equilibrium. Some 56 different evolutionary sequences have been calculated to allow an exploration of a sufficiently large volume of parameter space. The emphasis has been put on the DAV phenomenon and the effects of various parameters on the pulsation properties of models of DA white dwarfs. Models have been computed for three masses: M/M⊙ = 0.4, 0.6, and 0.8, respectively. In addition, the helium layer mass has been varied in the range -10 ≤ log [M(He)/M] ≤ -2, and the hydrogen layer mass in the range -14 ≤ log [M(H)/M] ≤ -4. The effects of varying the assumed convective efficiency have been investigated by calculating models with three different versions of the mixing-length theory. This is particularly important in the context of pulsating white dwarfs because mode driving occurs near the base of the superficial convection zone associated with the partial ionization zone of the main atmospheric constituent (either H in DA stars or He in DB stars). A special sequence has been computed to explore the effects of changing the composition gradient scale height in transition regions. Furthermore, models using two different sets of radiative opacities for the same compositions have been obtained to test the sensitivity of the pulsation properties to this component of the constitutive physics. Coupled with the excellent effective temperature coverage of the instability strips provided by the evolutionary sequences, these experiments constitute, by far, the most extensive study that has been carried out to provide suitable models for pulsating white dwarfs. The equilibrium models are also of interest for and have been used in studies of meridional circulation and differential rotation in white dwarfs. They are likewise of direct relevance to the theory of the spectral evolution of white dwarfs. In particular, the models provide ideal backgrounds in which to study diffusion processes of trace heavy elements in white dwarfs. The models also bear on the question of convective mixing in DA white dwarfs, which is of interest for both the pulsating DAV stars and the spectral evolution of white dwarfs in general. The basic cooling and structural properties of the evolutionary models are discussed extensively. It is first established that the cooling characteristics of the models compare well with those of contemporary white dwarf evolutionary calculations in the range of luminosities of interest. Advantage is next taken of the fact that several parameters have been varied to study, in a differential sense, the effects of these parameters on the cooling properties of the models. In particular, an important characteristic of white dwarf cooling is the relationship between the luminosity and the core temperature, and the effects of model parameters on this relationship are thoroughly discussed. The changing structure of the superficial convection zone, which appears as a white dwarf cools, is also discussed in the context of pulsating white dwarfs. Short of full-fledged pulsation calculations, use is made of a simple physical argument which suggests that there exists a relationship between the location of the base of the convection zone (associated with a potential driving region) and the corresponding value of the effective temperature at the blue edge of the instability strip. In this context, it is found that the expected theoretical blue edge temperature is mostly sensitive to the assumed convective efficiency, raising the possibility of calibrating the mixing-length theory in pulsating white dwarfs as already claimed by our group. The evolution of the profiles of several variables is next presented in extensive graphical form for typical sequences of cooling white dwarfs. This provides typical values for these variables as well as a thorough qualitative understanding of the main features of white dwarf evolution at intermediate luminosities. Finally, a potentially very useful seismological tool for white dwarfs is discussed: asymptotic pulsation theory shows that, in a first approximation, period spacings for high-order modes should be uniform, and that the magnitudes of the spacings depend uniquely on the structural properties of a model. Asymptotic period spacings are computed for a very large number of models, their dependence on model parameters is investigated, and their usefulness as seismological probes is assessed.
