﻿858 
  Dr. 
  N. 
  Bohr 
  on 
  the 
  Constitution 
  

  

  Such 
  a 
  conception, 
  however, 
  cannot 
  be 
  utilized 
  in 
  con- 
  

   sidering 
  the 
  formation 
  o£ 
  a 
  system 
  containing 
  more 
  than 
  a 
  

   single 
  nucleus 
  ; 
  for 
  in 
  the 
  latter 
  case 
  there 
  will 
  be 
  nothing 
  

   to 
  keep 
  the 
  nuclei 
  together 
  during 
  the 
  binding 
  of 
  the 
  

   electrons. 
  In 
  this 
  connexion 
  it 
  may 
  be 
  noticed 
  that 
  while 
  a 
  

   single 
  nucleus 
  carrying 
  a 
  large 
  positive 
  charge 
  is 
  able 
  to 
  

   bind 
  a 
  small 
  number 
  of 
  electrons, 
  on 
  the 
  contrary, 
  two 
  nuclei 
  

   highly 
  charged 
  obviously 
  cannot 
  be 
  kept 
  together 
  by 
  the 
  

   help 
  of 
  a 
  few 
  electrons. 
  We 
  must 
  therefore 
  assume 
  that 
  

   configurations 
  containing 
  several 
  nuclei 
  are 
  formed 
  by 
  the 
  

   interaction 
  of 
  systems- 
  — 
  each 
  containing 
  a 
  single 
  nucleus 
  — 
  

   which 
  already 
  have 
  bound 
  a 
  number 
  of 
  electrons. 
  

  

  § 
  2 
  deals 
  with 
  the 
  configuration 
  and 
  stability 
  of 
  a 
  system 
  

   already 
  formed. 
  We 
  shall 
  consider 
  only 
  the 
  simple 
  case 
  of 
  a 
  

   system 
  consisting 
  of 
  two 
  nuclei 
  and 
  of 
  a 
  ring 
  of 
  electrons 
  

   rotating 
  round 
  the 
  line 
  connecting 
  them 
  ; 
  the 
  result 
  of 
  the 
  

   calculation, 
  however, 
  gives 
  indication 
  of 
  what 
  configurations 
  

   are 
  to 
  be 
  expected 
  in 
  more 
  complicated 
  cases. 
  As 
  in 
  the 
  

   former 
  papers, 
  we 
  shall 
  assume 
  that 
  the 
  conditions 
  of 
  

   equilibrium 
  can 
  be 
  deduced 
  by 
  help 
  of 
  the 
  ordinary 
  mechanics. 
  

   In 
  determining 
  the 
  absolute 
  dimensions 
  and 
  the 
  stability 
  of 
  

   the 
  systems,, 
  however, 
  we 
  shall 
  use 
  the 
  main 
  hypothesis 
  of 
  

   Part 
  I. 
  According 
  to 
  this, 
  the 
  angular 
  momentum 
  of 
  every 
  

   electron 
  round 
  the 
  centre 
  of 
  its 
  orbit 
  is 
  equal 
  to 
  a 
  universal 
  

  

  value 
  ^— 
  ' 
  where 
  h 
  is 
  Planck's 
  constant 
  ; 
  further, 
  the 
  

  

  stability 
  is 
  determined 
  by 
  the 
  condition 
  that 
  the 
  total 
  energy 
  

   of 
  the 
  system 
  is 
  less 
  than 
  in 
  any 
  neighbouring 
  configuration 
  

   satisfying 
  the 
  same 
  condition 
  of 
  the 
  angular 
  momentum 
  of 
  

   the 
  electrons. 
  

  

  In 
  § 
  3 
  the 
  configuration 
  to 
  be 
  expected 
  for 
  a 
  hydrogen 
  

   molecule 
  is 
  discussed 
  in 
  some 
  detail. 
  

  

  § 
  4: 
  deals 
  with 
  the 
  mode 
  of 
  formation 
  of 
  the 
  systems. 
  A 
  

   simple 
  method 
  of 
  procedure 
  is 
  indicated, 
  by 
  which 
  it 
  is 
  

   possible 
  to 
  follow, 
  step 
  by 
  step, 
  the 
  combination 
  of 
  two 
  atoms 
  

   to 
  form 
  a 
  molecule. 
  The 
  configuration 
  obtained 
  will 
  be 
  

   shown 
  to 
  satisfy 
  the 
  conditions 
  used 
  in 
  § 
  2. 
  The 
  part 
  played 
  

   in 
  the 
  considerations 
  by 
  the 
  angular 
  momentum 
  of 
  the 
  

   electrons 
  strongly 
  supports 
  the 
  validity 
  of 
  the 
  main 
  h} 
  r 
  po- 
  

   thesis. 
  

  

  § 
  5 
  contains 
  a 
  few 
  indications 
  of 
  the 
  configurations 
  to 
  be 
  

   expected 
  for 
  systems 
  containing 
  a 
  greater 
  number 
  of 
  

   electrons. 
  

  

  