Magic numbers

Shell model

The nucleuses with so called "magic number" of nucleons have an extreme stability, i.e. the highest binding energy.

Shell model assumes this sequence of numbers:

      (1)(2)(3)(4) (5) (6)
--------------------------
       2  2  2  2   2   2
          6  6  6   6   6
            12 12  12  12
               30  30  30
                   32  32
                       44
--------------------------
total  2  8 20 50  82 126

Let us rewrite the previous scheme another way:

     (1)(2)(3)(4)(5)(6) (7)
--------------------------------------
 2    2  x  2  2  2  2   2    Helium
 6       6  x  6  6  6   6    Carbon
12         12  x 12 12  12    Magnesium
20            20  x 20  20    Calcium
30               30  x  30    Zinc
42                  42   x    Molybdenum
56                      56    Barium
--------------------------------------
total 2  6 14 28 50 82 126

Missing numbers 8 and 20 can be written: 8=2+6 and 20=2+6+12 (similarly 40= 2+6+12+20, 38= 6+12+20, 64= 2+12+20+30). Here is an inverse of the previous diagram:

     (1)(2)(3)(4)(5)(6)(7)
--------------------------------------
 2    *  2  *  *  *  *  *     Helium
 6       *  6  *  *  *  *     Carbon
12          * 12  *  *  *     Magnesium
20             * 20  *  *     Calcium
30                * 30  *     Zinc
42                   * 42     Molybdenum
56                      *     Barium
--------------------------------------
total 2  6 14 28 50 82 126

Sequence M(s)

Let number s be a shell number. We define number M(s):

M(s) = m1(s)-m2(s) = 1/3 s(s+1)(s+2) - s(s-1)

 s       0   1   2   3   4   5   6   7   8   9  10
---------------------------------------------------
 m1(s)   0   2   8  20  40  70 112 168 240 330 440
 m2(s)   0   0   2   6  12  20  30  42  56  72  90
---------------------------------------------------
 M(s)    0   2   6  14  28  50  82 126 184 258 350

Numbers M(s) makes arithmetic progression of the 3-th degree.

  0   2   6  14  28  50  82 126 184
     2   4   8  14  22  32  44  58
        2   4   6   8  10  12  14
          2   2   2   2   2   2

Nuclear and electron shells

Structure of periodic table is not definitive yet. (Even it is not known if it has finite or infinite number of elements.)

Sequence of electron shells:

    0,2,8,18,32, .. i.e.   2*n^2
Particular orbits (s-p-d-f):
1s	00	                    0 0     1
--------------------------------------
2s	00	                    1 0
2p	01 10 11	            1 1     4
--------------------------------------
3s	00	                    2 0
3p	01 10 11	            2 1
3d	02 20 12 21 22	        2 2     9
--------------------------------------
4s	00	                    3 0
4p	01 10 11	            3 1
4d	02 20 12 21 22	        3 2
4f  03 30 13 31 23 32 33	3 3    16
--------------------------------------
.....
Sequence of nuclear shells:
    0,2,6,12,20,30,42, .. i.e.   n*(n+1)= n^2+n

In the following diagram are the both sequences,
the first one: totals in vertical direction,
the second one: values in horizontal direction.

--+----------------------------------
 0|  1-1
 2|  1+1 4-2
 6|      4+2 9-3
12|          9+3 16-4
20|              16+4 25-5
30|                   25+5 36-6
42|                        36+6 49-7
56|                             49+7
--+----------------------------------
      2   8   18  32   50    72   98

Equivalence classes

Periodic table reminds mathematical structures (groups of equivalence classes,...)

Also e.g. the beginning of table of stable isotopes is simple and well structured:

 00         0
 01 H       1     2
 02 He      3     4
 03 Li      6     7
--------------------
 04 Be      9
 05 B      10    11
 06 C      12    13
 07 N      14    15
-------------------------
 08 O      16    17    18
 09 F      19
 10 Ne     20    21    22
 11 Na     23
-------------------------
 12 Mg     24    25    26
 13 Al     27
 14 Si     28    29    30
 15 P      31
--------------------------


Atoms