diff --git a/Makefile b/Makefile
index 433a65c..76b84fc 100644
--- a/Makefile
+++ b/Makefile
@@ -25,9 +25,21 @@ BINDIR = $(BASEDIR)bin/
 # Set the compiler choice
 #CXX = g++
 CXX = /usr/local/bin/g++
+# On OS X, using a separate installation of llvm tools:
+# CXX = /usr/local/opt/llvm/bin/clang++ -Xpreprocessor -fopenmp -lomp -L/usr/local/opt/llvm/lib:lib/ -I/usr/local/opt/llvm/include
+# CXX = clang++ -Weverything -ferror-limit=1
+# CXX += -Wno-padded -Wno-c++98-compat-pedantic -Wno-exit-time-destructors
+# CXX += -Wno-unused-parameter -Wno-global-constructors -Wno-sign-conversion -Wno-documentation -Wno-weak-vtables -Wno-unused-variable -Wno-shadow -Wno-float-conversion -Wno-float-equal -Wno-shorten-64-to-32 -Wno-conditional-uninitialized -Wno-unreachable-code -Wno-missing-prototypes -Wno-missing-variable-declarations -Wno-deprecated -Wno-documentation-unknown-command -Wno-zero-as-null-pointer-constant
+#CXXFLAGS = -std=c++14 -fopenmp
+CXXFLAGS = -fopenmp
+LDFLAGS = -L$(LIBDIR)
+LDLIBS = -l$(VERSION)
+INC = -I$(HEADDIR)
+
 MPICXX = mpicxx
 
 
+
 #COMPILE = g++ -Wall -I$(BASEDIR)include/ -L$(LIBDIR) -O3 -stdlib=libstdc++
 #COMPILE = g++ -Wall -I$(BASEDIR)include/ -L$(LIBDIR) -O3
 #COMPILE = g++ -I$(BASEDIR)include/ -L$(LIBDIR) -O3 -w -fopenmp
@@ -37,6 +49,9 @@ COMPILE = $(CXX) -I$(BASEDIR)include/ -L$(LIBDIR) -O3 -w -fopenmp
 COMPILE_MPI = mpicxx -I$(BASEDIR)include/ -L$(LIBDIR) -O3 -w -fopenmp
 #COMPILE_OMP = g++ -I$(BASEDIR)include/ -L$(LIBDIR) -O3 -w -fopenmp
 
+#COMPILE = $(CXX) $(CXXFLAGS) $(INC) $(LDFLAGS)
+#COMPILE = $(CXX)
+
 VPATH = $(SRCDIR)BETHE:$(SRCDIR)LIEBLIN:$(SRCDIR)COMBI:$(SRCDIR)EXECS:$(SRCDIR)FITTING:$(SRCDIR)HEIS:$(SRCDIR)INTEG:$(SRCDIR)MATRIX:$(SRCDIR)NRG:$(SRCDIR)ODSLF:$(SRCDIR)SCAN:$(SRCDIR)TBA:$(SRCDIR)UTILS:$(SRCDIR)XXX_VOA:$(SRCDIR)XXZ_VOA:$(SRCDIR)YOUNG
 
 vpath %.h $(HEADDIR)
diff --git a/include/ABACUS.h b/include/ABACUS.h
index 3b23635..30bdb59 100644
--- a/include/ABACUS.h
+++ b/include/ABACUS.h
@@ -17,7 +17,7 @@ Purpose:  Core header file, includes all descendents.
 
 // This core header file includes all the others
 
-const char ABACUS_VERSION[20] = "ABACUS++G_8";
+const char ABACUS_VERSION[20] = "ABACUS_0a";
 
 // Standard includes
 #include <cmath>
diff --git a/src/HEIS/Heis.cc b/src/HEIS/Heis.cc
index a6882ab..e6d779c 100644
--- a/src/HEIS/Heis.cc
+++ b/src/HEIS/Heis.cc
@@ -556,8 +556,23 @@ namespace ABACUS {
 	}
 
 	Ix2_min[j] = -Ix2_max[j];
+
+	Ix2_max[j] += 4;
+	Ix2_min[j] -= 4;
       }
 
+      // New attempt
+      // for (int j = 0; j < RefChain.Nstrings; ++j) {
+      // 	sum1 = 0;
+      // 	for (int k = 0; k < RefChain.Nstrings; ++k) {
+      // 	  sum1 += (j == k ? 0 : Nrap[k] * 2 * ABACUS::min(RefChain.Str_L[j], RefChain.Str_L[k]));
+      // 	}
+      // 	Ix2_max[j] = RefChain.Nsites - (2 * RefChain.Str_L[j] - 1) * (Nrap[j] - 1) - sum1;
+      // 	Ix2_min[j] = -Ix2_max[j] + 2;
+      // Ix2_max[j] += 2;
+      // Ix2_min[j] -= 2;
+      //}
+
     } // if XXZ_gpd
 
   }
diff --git a/src/HEIS/XXZ_gpd_Bethe_State.cc b/src/HEIS/XXZ_gpd_Bethe_State.cc
index f824ba0..b2bb065 100644
--- a/src/HEIS/XXZ_gpd_Bethe_State.cc
+++ b/src/HEIS/XXZ_gpd_Bethe_State.cc
@@ -192,6 +192,25 @@ namespace ABACUS {
       for (int alpha = 0; alpha < base[j]; ++alpha)
 	if ((Ix2[j][alpha] < -chain.Nsites) || (Ix2[j][alpha] >= chain.Nsites)) answer = false;
 
+    // Check that sum over quantum numbers fits in fundamental interval
+    int sumI = 0;
+    for (int j = 0; j < chain.Nstrings; ++j)
+      for (int alpha = 0; alpha < base[j]; ++alpha)
+	sumI += Ix2[j][alpha];
+    if (sumI < -chain.Nsites + 2 || sumI > chain.Nsites) answer = false;
+
+    // Check max distance between min and max quantum numbers at each level:
+    for (int j = 0; j < chain.Nstrings; ++j) {
+      int sum1 = 0;
+      for (int k = 0; k < chain.Nstrings; ++k) {
+	sum1 += (j == k) ? 0 : 2 * base[k] * ABACUS::min(chain.Str_L[j], chain.Str_L[k]);
+	if (base[j] > 0 &&
+	    (Ix2[j][base[j] - 1] - Ix2[j][0]
+	     >= 2*(chain.Nsites - (2*chain.Str_L[j] - 1) * base[j] - sum1)))
+	  answer = false;
+      }
+    }
+
     if (!answer) {
       E = 0.0;
       K = 0.0;
diff --git a/src/SCAN/General_Scan.cc b/src/SCAN/General_Scan.cc
index 150c05b..352c332 100644
--- a/src/SCAN/General_Scan.cc
+++ b/src/SCAN/General_Scan.cc
@@ -213,7 +213,6 @@ namespace ABACUS {
     // A paralevel == 2 branching's files have a suffix of the form "_3_8_2_8", meaning that this
     //  is the rank 2 out of 8 subscan of the _3_8 scan.
 
-
     bool in_parallel = (paralevel > 0);
     if (in_parallel && (rank.size() != paralevel || nr_processors.size() != paralevel)) {
       cout << "paralevel = " << paralevel << "\trank.size() = " << rank.size()