Wednesday, January 08, 2020

[nwuytyzf] Electron subshells

Electron subshells are named s, p, d, f, then alphabetically starting from g (or f):

spdfghijklmnopqrstuvwxyz

Of course, don't duplicate s and p:

spdfghijklmnoqrtuvwxyz

And j is omitted.  Reason might be because it looks too similar to i.  Reason might be because some language (Latin?) doesn't distinguish between i and j, or doesn't have j in its alphabet.  (Nowadays, however, I suspect any language that uses the Latin alphabet can print the letter j, if only to be able to print foreign words.)  Thus, we get this subset and permutation of the alphabet:

spdfghiklmnoqrtuvwxyz

There isn't agreement of what should be the names after z.

After a bit of further research, we guess it was Italian that induced skipping j.  Italian has an official alphabet (promulgated by whom?) which omits j.  However, the Italian alphabet also omits k w x y, but they are permitted as subshell names, so maybe it wasn't Italian.

Each subshell corresponds to a quantum number l (lowercase L), starting at l=0 for subshell s.

The capacity of a subshell, the maximum number of electrons it can hold, is 4*l + 2.  The capacities of the first few subshells are 2, 6, 10...  The expression 4*l+2 is the product of the 2 possible spin states for electrons (typically named -1/2 and +1/2) and the possibilities of the quantum number m ranging from -l to l (so 2*l+1 possibilities for m).

Below, we list the subshells, their quantum numbers, and their capacities.

s l=0 capacity=2
p l=1 capacity=6
d l=2 capacity=10
f l=3 capacity=14
g l=4 capacity=18
h l=5 capacity=22
i l=6 capacity=26
k l=7 capacity=30
l l=8 capacity=34
m l=9 capacity=38
n l=10 capacity=42
o l=11 capacity=46
q l=12 capacity=50
r l=13 capacity=54
t l=14 capacity=58
u l=15 capacity=62
v l=16 capacity=66
w l=17 capacity=70
x l=18 capacity=74
y l=19 capacity=78
z l=20 capacity=82

The next unnamed subshell is

l=21 capacity=86

Assuming the Madelung rule remains true for arbitrarily high Z (atomic number) (which it almost certainly doesn't) the first element whose ground state has electrons in this unnamed subshell is Element 13245, untribiquadpentium (Utbqp).  It has one electron in its n=22, l=21 subshell.

Create a new naming scheme for subshells which is more regular and provides more useful information.  Probably name them by l or capacity or both.  Having l is useful because the Madelung rule predicts subshells fill in order of increasing n+l.

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