diff --git a/ChangeLog b/ChangeLog
index 04057dbe..c0398091 100644
--- a/ChangeLog
+++ b/ChangeLog
@@ -1,3 +1,5 @@
+Version 3.0.19  (2019-11-30):
+	* support fractional nuclear charges
 Version 3.0.18  (2019-07-02):
 	* Fix undefined varialbe in nabla-rinv integral
 	* Add integral < i | nabla-rinv | j >
diff --git a/README b/README
index 3a4d73c3..8424fb81 100644
--- a/README
+++ b/README
@@ -1,8 +1,8 @@
 libcint
 =======
 
-version 3.0.18
-2019-07-02
+version 3.0.19
+2019-11-30
 
 
 What is libcint
diff --git a/include/cint.h.in b/include/cint.h.in
index 49446902..1845741d 100644
--- a/include/cint.h.in
+++ b/include/cint.h.in
@@ -87,6 +87,7 @@
 #define ANG_MAX         12 // l = 0..11
 #define POINT_NUC       1
 #define GAUSSIAN_NUC    2
+#define FRAC_CHARGE_NUC 3
 
 #define bas(SLOT,I)     bas[BAS_SLOTS * (I) + (SLOT)]
 #define atm(SLOT,I)     atm[ATM_SLOTS * (I) + (SLOT)]
diff --git a/src/cint1e.c b/src/cint1e.c
index b74de0ca..d749d51b 100644
--- a/src/cint1e.c
+++ b/src/cint1e.c
@@ -230,6 +230,7 @@ FINT CINT1e_drv(double *out, FINT *dims, CINTEnvVars *envs,
         FINT n;
         FINT has_value = 0;
         FINT *atm = envs->atm;
+        double *env = envs->env;
         double charge_fac;
 
         CINTdset0(nc*n_comp, gctr);
@@ -245,8 +246,14 @@ FINT CINT1e_drv(double *out, FINT *dims, CINTEnvVars *envs,
                 break;
         default:
                 for (n = 0; n < envs->natm; n++) {
-                        if (atm(CHARGE_OF,n) != 0) {
+                        if (atm(NUC_MOD_OF,n) == FRAC_CHARGE_NUC) {
+                                charge_fac = -env[atm(PTR_FRAC_CHARGE,n)];
+                        } else if (atm(CHARGE_OF,n) != 0) {
                                 charge_fac = -abs(atm(CHARGE_OF,n));
+                        } else {
+                                charge_fac = 0;
+                        }
+                        if (charge_fac != 0) {
                                 has_value = CINT1e_nuc_loop(gctr, envs, charge_fac, n, cache)
                                         || has_value;
                         }
diff --git a/src/cint3c1e.c b/src/cint3c1e.c
index 2306f451..99b5ce4e 100644
--- a/src/cint3c1e.c
+++ b/src/cint3c1e.c
@@ -382,14 +382,22 @@ FINT CINT3c1e_cart_drv(double *out, FINT *dims, CINTEnvVars *envs, CINTOpt *opt,
                 FINT buf_filled;
                 double fac;
                 double *buf;
+                double *env = envs->env;
                 MALLOC_INSTACK(gctr, double, nc*n_comp);
                 MALLOC_INSTACK(buf, double, nc*n_comp);
                 for (i = 0; i < nc*n_comp; i++) {
                         gctr[i] = 0;
                 }
                 for (n = 0; n < envs->natm; n++) {
-                        if (atm(CHARGE_OF,n) != 0) {
+                        if (atm(NUC_MOD_OF,n) == FRAC_CHARGE_NUC) {
+                                fac = -env[atm(PTR_FRAC_CHARGE,n)];
+                        } else if (atm(CHARGE_OF,n) != 0) {
                                 fac = -abs(atm(CHARGE_OF,n));
+                        } else {
+                                fac = 0;
+                        }
+
+                        if (fac != 0) {
                                 buf_filled = CINT3c1e_nuc_loop_nopt(buf, envs, fac, n, cache);
                                 if (buf_filled) {
                                         for (i = 0; i < nc*n_comp; i++) {
diff --git a/src/cint_const.h b/src/cint_const.h
index ac2039f4..14a15075 100644
--- a/src/cint_const.h
+++ b/src/cint_const.h
@@ -23,6 +23,7 @@
 #define PTR_COORD       1
 #define NUC_MOD_OF      2
 #define PTR_ZETA        3
+#define PTR_FRAC_CHARGE 3
 #define RESERVE_ATMLOT1 4
 #define RESERVE_ATMLOT2 5
 #define ATM_SLOTS       6
@@ -113,3 +114,4 @@
 
 #define POINT_NUC       1
 #define GAUSSIAN_NUC    2
+#define FRAC_CHARGE_NUC 3