  We extend the Rome-Southampton regularization independent
momentum-subtraction renormalization scheme(RI/MOM) for bilinear operators to
one with a nonexceptional, symmetric subtraction point. Two-point Green's
functions with the insertion of quark bilinear operators are computed with
scalar, pseudoscalar, vector, axial-vector and tensor operators at one-loop
order in perturbative QCD. We call this new scheme RI/SMOM, where the S stands
for "symmetric". Conversion factors are derived, which connect the RI/SMOM
scheme and the MSbar scheme and can be used to convert results obtained in
lattice calculations into the MSbar scheme. Such a symmetric subtraction point
involves nonexceptional momenta implying a lattice calculation with
substantially suppressed contamination from infrared effects. Further, we find
that the size of the one-loop corrections for these infrared improved
kinematics is substantially decreased in the case of the pseudoscalar and
scalar operator, suggesting a much better behaved perturbative series.
Therefore it should allow us to reduce the error in the determination of the
quark mass appreciably.
