spell correction

input/negf/validation_studies/all_around_metal

@@ -1,7 +1,7 @@
 ###############################################################
 # Description:
 # This script models a (17, 0) carbon nanotube surrounded by a 
-# contant metal (Pd). Electrostatic potential is imposed
+# constant metal (Pd). Electrostatic potential is imposed
 # on the metal as "Gate.surf_soln_function" from GV_min=0V
 # to GV_max=1V. At each step, charge density on the nanotube
 # varies until self-consistency is achieved with respect to the