diff --git a/concha/get_contacts.ipynb b/concha/get_contacts.ipynb
index 918003bd865ff9bff13632999717a913860ee875..acd883a8b841f13bdb1aa2e109cf68d51db79751 100644
--- a/concha/get_contacts.ipynb
+++ b/concha/get_contacts.ipynb
@@ -69,8 +69,8 @@
     "    coor_conf['min_th2'] = np.nanmin([np.abs(np.arccos(coor_conf['or2_z']) - coor_conf['th21']),\n",
     "                                                   np.abs(np.arccos(coor_conf['or2_z']) - coor_conf['th22']), \n",
     "                                                   np.abs(np.arccos(coor_conf['or2_z']) - coor_conf['th23'])], axis = 0) \n",
-    "    coor_conf['dis_th1'] = 0.5*(np.sin(coor_conf.min_th1)**2*(coor_conf.min_th1 < np.pi/2) + (1 + np.cos(coor_conf.min_th1)**2)*(coor_conf.min_th1 >= np.pi/2))\n",
-    "    coor_conf['dis_th2'] = 0.5*(np.sin(coor_conf.min_th2)**2*(coor_conf.min_th2 < np.pi/2) + (1 + np.cos(coor_conf.min_th2)**2)*(coor_conf.min_th2 >= np.pi/2))\n",
+    "    coor_conf['dis_th1'] = 0.5*(np.sin(coor_conf.min_th1)**2*(coor_conf.min_th1 < np.pi/2) + (1 - np.cos(coor_conf.min_th1)**2)*(coor_conf.min_th1 >= np.pi/2))\n",
+    "    coor_conf['dis_th2'] = 0.5*(np.sin(coor_conf.min_th2)**2*(coor_conf.min_th2 < np.pi/2) + (1 - np.cos(coor_conf.min_th2)**2)*(coor_conf.min_th2 >= np.pi/2))\n",
     "    \n",
     "    alpha = beta = 0.5\n",
     "    coor_conf['dis_r3'] = np.sqrt(coor_conf.coor_x**2 + coor_conf.coor_y**2 + coor_conf.coor_z**2)\n",