diff --git a/src/USER-OMP/fix_qeq_reax_omp.cpp b/src/USER-OMP/fix_qeq_reax_omp.cpp
index 3ca193be74d3bb1f46d6ee411928971000e6caa0..df586132d4aad785d017c45068436222292c68a2 100644
--- a/src/USER-OMP/fix_qeq_reax_omp.cpp
+++ b/src/USER-OMP/fix_qeq_reax_omp.cpp
@@ -172,6 +172,7 @@ void FixQEqReaxOMP::compute_H()
     H.firstnbr[ai] = num_nbrs;
     num_nbrs += numneigh[ai];
   }
+  m_fill = num_nbrs;
 
   // fill in the H matrix