ATOM
@
Solid
consists of some atoms, each of which consists of one nucleus and some
electrons. All electrons attributing to one neutral atom interact electrostatically
with the nucleus. Some electrons among them can interact with electrons
in another atom. The latter interaction contributes to the aggregation
of atoms.
This
section describes the electron configuration of atom through examining
both electrostatic and electromagnetic interactions occurring on an atom.
Pauli exclusion rule and Hunt's rule may be easily derived through examining
these two kinds of interaction.
1.Introduction.
An
atom has Z electrons and one nucleus with the positive electric charge
Ze(Z: atomic number, e: electron charge). These electrons in the atom turn
around the nucleus along the orbit called an atomic orbital. These electrons
are called shell electrons.
The
orbit of revolution of electron is defined through examining quantum-mechanically
both the kinetic motion and the electrostatic interaction with the positive
electric charge of the nucleus. The atomic orbital is always characterized
geometrically with the following three kinds of quantum numbers: principle
quantum number N, azymuthal quantum number L and magnetic quantum
number M. The value of L is constrained by N and the value of M
is by L (L:
one of 0,1,2,3..(N-1) ) (M: one of -L,-(L-1),..0.,,(L-1),L
).
The principle quantum numbers 1, 2, 3, 4, 5, 6 can be represented by K,L,M,N,O,P,
respectivelyly. Each atomic orbital is defined by use of these three
numbers. For example, the atomic orbital 2p1 indicates
the orbital defined by principle quantum number 2, azymuthal quantum number
1 and the magnetic quantum number 1(underscript 1).
All
orbitals defined by N ( different on azymuthal and magnetic quantum number,
respectively) are theoretically at the same energy level as EN.
2.
Electron Configuration of atom
All
shell electrons of atom are accommodated by some atomic orbitals. But,
we must remark that the properties of orbital, defined by use of the classical
Schrodinger equation, does not correctly represent the properties of atomic
orbital occupied by electron.
These
above orbitals is determined without taking into accout of the electromagnetic
field dependent on the kinds of revolutions( clockwise or anti-clockwise).
The circuit with the clockwise revolution is electromagnetically different
from the other anti-clockwise circuit.
Then,
the physical characteristics of orbital, defined by use of the equation
only, does not correctly represent the physical characteristics of the
orbital occupied by electron,
Classical
Schrodinger's equation of an atom regards both clockwise and anti-clockwise
momentum as the same quantity.
This
constrained viewpoint is caused by Heisenberg's uncertainty rule, which
means that it is impossible to determine both energy E and time t of particle
simultaneously.
Et > h
The
direction of the revolution of electron is determined by taking into account
of time-axis.
Therefore,
it is very hard to find in the classical Schrodinger solution the direction
of the revolution. Neglecting time-axis, we regard both kinds of revolutions
(clockwise and anti-clockwise) as the same orbital.
As
one convenient method to avoid from the above constraint brought about
by Heisenberg's rule, we would imagine the method to substitute the problem
of the momentum direction described above for it of the self-rotation.
The substitution indicates that spin(eigen-angular momentum) is independent
from the angular momentum dependent on space.
However,
it is never allowable to apply this substitution method to an atom system
including the electromagnetic field, because of the above reason. If we
applied the method to some heavy atom system, we would meet with the difficulty
to inpterpret the reason why these atoms have the higher magnetic-susceptibility
than light atoms. |
We
must remark that the sign of the magnetic quantum number is defined
through examining geometrically the absolute
angular
momentum of electron on atomic orbital.
The magnetic quantum number means the geometrical parameter to define the
geometrical area made by momentum*radius. If we see the orbital by use
of the polar coordinate axes(r,f,and
j)
the principle quantum number, the azymuthal quantum number and the magnetic
quantum number may are obtained through quantum-mechanical examinations
about r, f,and
j,
respectively. Both signs of magnetic quantum number corresponds to both
positive and negative signs of the inclined angle against the standard
plane, respectively ( -90 <= angle <= 90 degree).
We
know that p-1, p0
and p1 , deduced by the Schrodinger's
equation are different from experimental px,py
and pz occupied by electron,
respectively. We must remark that the former orbitals are determined without
taking into account of the revolution-direction. and that the latter
p orbitals, occupied by electron, are configurated so that these mutual
electro-magnetic interactions may be reduced. The above discussions suggest
explicitly that the difference is caused by the mutual electro-magnetic
interaction.
I
do not like some magic explanations so much, which means that an orbital
occupied by electron is given by examinig the wavefunction-phases of these
orbitals unoccupied by electron. |
Please
send me any suggestions and comments,
if you find any practical viewpoints. Your comments will be adopted in
this Page as possible as I can.Next:
See you again next
time. You will see the detailed electron configurations of each atom at
the next page.