  Studies of structure-property relationships in spintronics are essential for
the design of materials that can fill specific roles in devices. For example,
materials with low symmetry allow unconventional configurations of
charge-to-spin conversion which can be used to generate efficient spin-orbit
torques. Here, we explore the relationship between crystal symmetry and
geometry of the Rashba-Edelstein effect (REE) that causes spin accumulation in
response to an applied electric current. Based on a symmetry analysis performed
for 230 crystallographic space groups, we identify classes of materials that
can host conventional or collinear REE. Although transverse spin accumulation
is commonly associated with the so-called 'Rashba materials', we show that the
presence of specific spin texture does not easily translate to the
configuration of REE. More specifically, bulk crystals may simultaneously host
different types of spin-orbit fields, depending on the crystallographic point
group and the symmetry of the specific $k$-vector, which, averaged over the
Brillouin zone, determine the direction and magnitude of the induced spin
accumulation. To explore the connection between crystal symmetry, spin texture,
and the magnitude of REE, we perform first-principles calculations for
representative materials with different symmetries. We believe that our results
will be helpful for further computational and experimental studies, as well as
the design of spintronics devices.
