and because we seek the value of outside the molecule, (IIIb) is transformed into
or, due to (35), it is transformed into
If we bring the last two terms on the left side, then we just obtain or , as it can be seen by (Vb); since and only differ by magnitudes of order , we may replace the vector product (Vb) by .
From
we obtain by integration; constants were omitted by us, since we are only dealing with vibrations.
We substitute the values (39) and put
It is then
(40)
and namely, , , are still related to the instant given above.
As to how the other magnitudes occurring in (Ib)-(VIIb) can be determined, can immediately be seen.
§ 34. Just some words on the error committed in the above calculation. That in (38) the factor was replaced by , needs surely no justification. But we also haven't taken the values of for the function f at the the correct times. Once we have replaced by in (38), then in the time when l is one of the