Micromeritics ASAP 2460, Operator'S Manual

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Appendix C ASAP 2460 Operator’s Manual
C-30 246-42800-01 - Aug 2013
Interaction Parameter
The interaction parameter (IP) results from the following calculations:
The Kirkwood-Muller dispersion coefficients
where

A
= polarizability of gas molecule (cm
3
)

S
= polarizability of sample atoms (cm
3
)
mc
2
= kinetic energy of electron (0.8183 × 10
-6
erg)

A
= diamagnetic susceptibility of gas molecule (cm
3
)

where:
N
A
= number of gas molecules/cm
2
at monolayer from the
Horvath-Kawa-
zoe Physical Properties
window
N
S
= number of sample atoms/cm
2
from the
Horvath-Kawazoe Physical
Properties
window

S
= diamagnetic susceptibility of sample atom (cm
3
)
Refer to
Interaction Parameter Components
, page
C-32
for recommended values.
A
S
6 mc
2
a
S
a
A

S

S
------

A

A
-------
+
--------------------------
=
A
A
3 mc
2

A

A
2
---------------------------
=
IP N
A
A
A
 
N
S
A
S
 
+ =