From aaba7369678b38cb9c25daf31b09b593b839e70d Mon Sep 17 00:00:00 2001
From: "Aidan P. Thompson" <athomps@attaway-login2.sandia.gov>
Date: Sat, 24 Feb 2024 14:14:52 -0700
Subject: [PATCH] Fixed error in forces that only affects non-zero t1m MS-MEAM
 models

---
 src/KOKKOS/meam_force_kokkos.h | 2 ++
 src/MEAM/meam_force.cpp        | 2 ++
 2 files changed, 4 insertions(+)

diff --git a/src/KOKKOS/meam_force_kokkos.h b/src/KOKKOS/meam_force_kokkos.h
index fec923f5b2..2f0c51dddb 100644
--- a/src/KOKKOS/meam_force_kokkos.h
+++ b/src/KOKKOS/meam_force_kokkos.h
@@ -601,6 +601,8 @@ KOKKOS_INLINE_FUNCTION void MEAMKokkos<DeviceType>::operator()(TagMEAMForce<NEIG
             drho2mds2 = a2 * rhoa2mi * arg1j2m - 2.0 / 3.0 * d_arho2mb[j] * rhoa2mi;
             drho3mds1 = a3 * rhoa3mj * arg1i3m - a3a * rhoa3mj * arg3i3m;
             drho3mds2 = a3 * rhoa3mi * arg1j3m - a3a * rhoa3mi * arg3j3m;
+            drho1mds1 *= -1;
+            drho1mds2 *= -1;
             drho3mds1 *= -1;
             drho3mds2 *= -1;
           } else {
diff --git a/src/MEAM/meam_force.cpp b/src/MEAM/meam_force.cpp
index 23230e0fbc..4ee3cd4f83 100644
--- a/src/MEAM/meam_force.cpp
+++ b/src/MEAM/meam_force.cpp
@@ -533,6 +533,8 @@ void MEAM::meam_force(int i, int eflag_global, int eflag_atom, int vflag_global,
             drho2mds2 = a2 * rhoa2mi * arg1j2m - 2.0 / 3.0 * arho2mb[j] * rhoa2mi;
             drho3mds1 = a3 * rhoa3mj * arg1i3m - a3a * rhoa3mj * arg3i3m;
             drho3mds2 = a3 * rhoa3mi * arg1j3m - a3a * rhoa3mi * arg3j3m;
+            drho1mds1 *= -1;
+            drho1mds2 *= -1;
             drho3mds1 *= -1;
             drho3mds2 *= -1;
           } else {