diff --git a/Makefile b/Makefile
index 75daf8e..afb3003 100644
--- a/Makefile
+++ b/Makefile
@@ -1,30 +1,34 @@
-EXEC=gradz_n2n_fd4_omp gradz_n2n_fd4_cuda gradz_n2n_fd4_acc  gradz_n2n_fd4_omp_nv gradz_n2n_fd4_omp gradz_n2n_fd4_omp_nv gradz_n2n_fd4_off gradz_n2n_fd4_acc
+EXEC=gradz_n2n_fd4_omp_nv gradz_n2n_fd4_cuda gradz_n2n_fd4_acc_nv gradz_n2n_fd4_omp_nv gradz_n2n_fd4_omp gradz_n2n_fd4_acc_gcc 
 # on izar
 #FC=gfortran # GNU Fortran compiler
 
-FCBIN=/scratch/software/spack/opt/spack/linux-rhel7-sandybridge/gcc-4.8.5/gcc-9.3.0-rv7cc5ibshxf6lldza2ym3wtjormh5cl/bin/gfortran
+#FCBIN=/scratch/software/spack/opt/spack/linux-rhel7-sandybridge/gcc-4.8.5/gcc-9.3.0-rv7cc5ibshxf6lldza2ym3wtjormh5cl/bin/gfortran
+FCBIN=/home/foureste/Projects/gcc-11.2.0/bin/gfortran
 #FCBIN=gfortran
 FC=nvfortran # NVHPC Fortran compiler
 #
 FCFLAGS= -O3 -fopenmp -lgfortran -lm -foffload="-lm -lgfortran" # options for OpenMP with GNU
+FCFLAGS_ACC= -O3 -fopenacc -lgfortran -lm # options for OpenMP with GNU
 #FLAGS=-O3 -Xcompiler "-march=skylake -mprefer-vector-width=512"
 FLAGS= -tp=skylake -O3 -mavx512f #-ccbin=$(CCBIN)
 FLAGS_OMP  = -ta=host # options for openMP with NVHPC
 FLAGS_OFF  = -static-nvidia -mp=gpu -gpu=cc70 # options for openMP with NVHPC
 FLAGS_ACC  = -acc -gpu=cc70 # options for openACC with NVHPC
 FLAGS_CUDA = -cuda -gpu=cc70 -g
 #
 all: $(EXEC)
 
 gradz_n2n_fd4_cuda: gradz_n2n_fd4.F90 gradients_mod.F90 space_grid_mod.F90 prec_const_mod.F90
-	$(FC) $(FLAGS_CUDA) prec_const_mod.F90 space_grid_mod.F90 gradients_mod.F90 gradz_n2n_fd4.F90 -o $@
+	$(FC) $(FLAGS) $(FLAGS_CUDA) prec_const_mod.F90 space_grid_mod.F90 gradients_mod.F90 gradz_n2n_fd4.F90 -o $@
 gradz_n2n_fd4_omp: gradz_n2n_fd4.F90 gradients_mod.F90 space_grid_mod.F90 prec_const_mod.F90
 	$(FCBIN) $(FCFLAGS) prec_const_mod.F90 space_grid_mod.F90 gradients_mod.F90 gradz_n2n_fd4.F90 -o $@
+
+gradz_n2n_fd4_acc_gcc: gradz_n2n_fd4.F90 gradients_mod.F90 space_grid_mod.F90 prec_const_mod.F90
+	$(FCBIN) -O3 -lgfortran -lm $(FCFLAGS_ACC) prec_const_mod.F90 space_grid_mod.F90 gradients_mod.F90 gradz_n2n_fd4.F90 -o $@
+
 gradz_n2n_fd4_omp_nv: gradz_n2n_fd4.F90 gradients_mod.F90 space_grid_mod.F90 prec_const_mod.F90
-	$(FC) $(FLAGS_OFF) prec_const_mod.F90 space_grid_mod.F90 gradients_mod.F90 gradz_n2n_fd4.F90 -o $@
-gradz_n2n_fd4_off: gradz_n2n_fd4.F90 gradients_mod.F90 space_grid_mod.F90 prec_const_mod.F90
 	$(FC) $(FLAGS) $(FLAGS_OFF) prec_const_mod.F90 space_grid_mod.F90 gradients_mod.F90 gradz_n2n_fd4.F90 -o $@
-gradz_n2n_fd4_acc: gradz_n2n_fd4.F90 gradients_mod.F90 space_grid_mod.F90 prec_const_mod.F90
-	$(FC) $(FLAGS_ACC) prec_const_mod.F90 space_grid_mod.F90 gradients_mod.F90 gradz_n2n_fd4.F90 -o $@
+gradz_n2n_fd4_acc_nv: gradz_n2n_fd4.F90 gradients_mod.F90 space_grid_mod.F90 prec_const_mod.F90
+	$(FC) $(FLAGS) $(FLAGS_ACC) prec_const_mod.F90 space_grid_mod.F90 gradients_mod.F90 gradz_n2n_fd4.F90 -o $@
 clean:
 	rm -f $(EXEC) *.mod *.o *~