DOC. 2 LAW OF
PHOTOCHEMICAL
EQUIVALENCE
93
^
=
E8W+Ö}'
SSs=
T8ni{cvMT+
cx-
R-
R\%^
where
one
has
to set
(4a')
Sn1 =
-1,
Sn2 =
+1,
Sn3 =
+1.
By
virtue
of
these
equations
for the variations and
equation (3), equation
(4)
takes
the form
(4a)
where
we
abbreviate
Ne
RT
+
lga
-
Ig(t
')"
"
(4a")
t
Ne
lga
=
+
6
RT
^E5wi|cv11sr
+
ci
-
R
~
S
-
j
The
quantity
denoted
by a
is
independent
of
Ts.
§3.
Conclusions
from
the
Condition
for
Equilibrium
We
now
write
(4a)
in the
form
a'
- -
(4b)
p
=
--e
RTs.
A
Since the relation
between
Ts
and
p
must
be
independent
of
T,
the
quantities
A'a/A
and
e
must
be
independent
of
T.
Since these
quantities are
also
independent
of
Ts,
we
thus arrive
at
the
relationship
between
p
and
Ts
that
corresponds
to
Wien's
radiation
formula. From this
we
conclude:
The
assumptions
about the
course
of
photochemical processes
postulated in
§1
are
compatible
with
the
empirically
known
law of thermal radiation
only
insofar
as
the
acting
radiation lies within the
range
of
validity
of Wien's
radiation
law;
but
in
that
case,
Wien's law is
a
consequence
of
our
assumptions.
If, introducing
Planck's
constant
we
write Wien's radiation formula in the form
87rftv3
kt
P
=
z-e
then
we see
by comparison
with
(4b)
that the
equations
(5)
e
= Av0,
(6)
=
87rhv°
c3
[8]
[9]