diff --git a/science/nwchem/Makefile b/science/nwchem/Makefile
index a55952eab3dc..8153ee5ab78c 100644
--- a/science/nwchem/Makefile
+++ b/science/nwchem/Makefile
@@ -1,69 +1,81 @@
 PORTNAME=	nwchem
 DISTVERSIONPREFIX=	v
 DISTVERSION=	7.0.2
 DISTVERSIONSUFFIX=	-release
-PORTREVISION=	1
+PORTREVISION=	2
 CATEGORIES=	science
 
 MAINTAINER=	yuri@FreeBSD.org
 COMMENT=	High-performance computational chemistry software
 
 LICENSE=	ECL20
 LICENSE_NAME=	Educational Community License (ECL) 2.0
 LICENSE_FILE=	${WRKSRC}/../LICENSE.TXT
 LICENSE_PERMS=	dist-mirror dist-sell pkg-mirror pkg-sell auto-accept
 
 BROKEN_aarch64=	fails to build: gfortran10: error: unrecognized command-line option '-m64'
 
 BUILD_DEPENDS=	bash:shells/bash
 LIB_DEPENDS=	libblas.so:math/blas \
-		libga.so:devel/ga \
-		libmpich.so:net/mpich
+		libga.so:devel/ga
 RUN_DEPENDS=	nwchem-data>0:science/nwchem-data
 
 USES=		fortran gmake perl5 shebangfix
 SHEBANG_FILES=	../contrib/distro-tools/build_* ../contrib/add_* config/64_to_32
 SHEBANG_GLOB=	*.sh
 USE_GITHUB=	yes
 GH_ACCOUNT=	nwchemgit
 USE_PERL5=	build
 
 MAKEFILE=	GNUmakefile
 ARCH_64BIT=	${ARCH:C/.*64.*/64/:S/${ARCH}//}
-MAKE_ENV=	NWCHEM_TOP=${WRKSRC}/.. NWCHEM_MODULES=all NWCHEM_LONG_PATHS=Y NWCHEM_TARGET=LINUX${ARCH_64BIT} USE_MPI=Y USE_INTERNALBLAS=Y EXTERNAL_GA_PATH=${LOCALBASE} \
+MAKE_ENV=	NWCHEM_TOP=${WRKSRC}/.. NWCHEM_MODULES=all NWCHEM_LONG_PATHS=Y NWCHEM_TARGET=LINUX${ARCH_64BIT} USE_INTERNALBLAS=Y EXTERNAL_GA_PATH=${LOCALBASE} \
 		BLAS_SIZE=4 USE_64TO32=y
 
 SUB_FILES=	nwchemrc
 
 WRKSRC_SUBDIR=	src
 
 BINARY_ALIAS=	gcc=${CC} gfortran=gfortran${GCC_DEFAULT}
 
 PLIST_FILES=	bin/nwchem etc/nwchemrc
 
 OPTIONS_DEFINE=		PYTHON
-OPTIONS_DEFAULT=	PYTHON
+OPTIONS_DEFAULT=	PYTHON MPICH # the default should be the same as for the MPI option in math/scalapack and devel/ga
+OPTIONS_RADIO=		MPI
+OPTIONS_RADIO_MPI=	NOMPI MPICH OPENMPI
+
+NOMPI_DESC=		MPI isn't used
+NOMPI_BROKEN=		Fails to build without MPI
+
+MPICH_MAKE_ENV=		USE_MPI=Y
+MPICH_LIB_DEPENDS=	libmpich.so:net/mpich
+
+OPENMPI_MAKE_ENV=	USE_MPI=Y PATH=${LOCALBASE}/mpi/openmpi/bin:$${PATH} # mpif90 in path determines which MPI library to use, see https://www.nwchem-sw.org/index-php/Compiling_NWChem.html#MPI_variables
+OPENMPI_BUILD_DEPENDS=	openmpi>0:net/openmpi
+OPENMPI_RUN_DEPENDS=	openmpi>0:net/openmpi
+OPENMPI_VARS=		CONFLICTS_BUILD=mpich
 
 PYTHON_DESC=		Enable Python syntax in input files
 PYTHON_USES=		python
 PYTHON_MAKE_ENV=	PYTHONVERSION=${PYTHON_VER} NWCHEM_MODULES="all python"
 
 post-extract:
 	@${RM} ${WRKSRC}/atomscf/src.orig
 
 post-patch:
 	@${REINPLACE_CMD} 's|nwchrc="/etc/nwchemrc"|nwchrc="${PREFIX}/etc/nwchemrc"|' ${WRKSRC}/util/util_nwchemrc.F
 
 pre-build:
 	@cd ${WRKSRC} && \
 		${SETENV} ${MAKE_ENV} ${MAKE_CMD} nwchem_config && \
 		${SETENV} ${MAKE_ENV} ${MAKE_CMD} 64_to_32
 
 do-install:
 	${INSTALL_DATA} ${WRKDIR}/nwchemrc ${STAGEDIR}${PREFIX}/etc/nwchemrc
 	${INSTALL_PROGRAM} ${WRKSRC}/../bin/LINUX${ARCH_64BIT}/${PORTNAME} ${STAGEDIR}${PREFIX}/bin/${PORTNAME}
 
 do-test:
 	@cd ${WRKSRC}/../QA && NWCHEM_TOP=${WRKSRC}/.. NWCHEM_TARGET=LINUX64 ./doqmtests.mpi
 
 .include <bsd.port.mk>