%chk=bh3_nbo.chk
%mem=200MB
%nproc=1
# b3lyp/3-21g geom=connectivity pop=nbo  

NBO analysis for bh3

0 1
 B
 H                  1              B1
 H                  1              B2    2              A1
 H                  1              B3    2              A2    3              D1

   B1             1.1945
   B2             1.1945
   B3             1.1945
   A1           120.0000
   A2           120.0000
   D1           180.0000

 1 2 1.0 3 1.0 4 1.0
 2
 3
 4