Some estimates for commutators of Riesz transforms associated with Schrödinger operators

We consider the Schrödinger operator L=−Δ+VL=−Δ+V on RnRn, where the nonnegative potential V   belongs to the reverse Hölder class Bq1Bq1 for some q1≥n2. Let q2=1q2=1 when q1≥nq1≥n and 1q2=1−1q1+1n when n2