  We present a prescription for parametrizing the chemical profile in the core
of white dwarfs in the light of the recent discovery that pulsation modes may
sometimes be deeply confined in some cool pulsating white dwarfs. Such modes
may be used as unique probes of the complicated chemical stratification that
results from several processes that occurred in previous evolutionary phases of
intermediate-mass stars. This effort is part of our ongoing quest for more
credible and realistic seismic models of white dwarfs using static,
parametrized equilibrium structures. Inspired from successful techniques
developed in design optimization fields (such as aerodynamics), we exploit
Akima splines for the tracing of the chemical profile of oxygen (carbon) in the
core of a white dwarf model. A series of tests are then presented to better
seize the precision and significance of the results that can be obtained in an
asteroseismological context. We also show that the new parametrization passes
an essential basic test, as it successfully reproduces the chemical
stratification of a full evolutionary model.
