98
4 Rotation of the Polyatomic Molecule
bands from different conformations of a molecule and for the analysis of molecular spectra when internal rotation, centrifugal distortion, nuclear quadrupole
coupling interactions, large-amplitude motions, and inertial-frame reorientation
effects are resolved. (https://www.nist.gov/services-resources/software/jb95-spe
ctral-fitting-program)
• AABS is a program for the assignment and analysis of broadband spectra (Kisiel
et al. 2005).
• PGOPHER is a program used for the automatic assignment and fitting of spectra
(Western and Billinghurst 2019).
A collection of programs for various aspects of the rotational spectroscopy
problem are available free of charge from http://www.ifpan.edu.pl/~kisiel/prospe.
htm.
Appendix 1
Centrifugal distortion correction for a planar molecule.
From the experimental quartic centrifugal distortion constants, it is possible to
determine a set of five determinable combinations (Watson 1977)
T xx = − J − 2δ J = −D J + 2d 1 + 2d 2
(4.48a)
T yy = − J + 2δ J = −D J − 2d 1 + 2d 2
(4.48b)
T zz = − J − J K − K = −D J − D J K − D K
(4.48c)
T 1 = −3 J − J K = −3D J − D J K − 6d 2
(4.48d)
T 2 = −(B x + B y + B z )) J −
1
2
(B x + B y )) JK + (B x − B y )(δ J + δ K )
= −(B x + B y + B z )D J −
1
2
(B x + B y )D J K −
1
2
(B x − B y )d 1 − 6B z d 2
(4.48e)
where the notation of Watson (1977) has been used
T αα =
1
4
τ αααα
(4.49a)
T αβ =
1
4
τ ααββ
(4.49b)
4 Rotation of the Polyatomic Molecule
bands from different conformations of a molecule and for the analysis of molecular spectra when internal rotation, centrifugal distortion, nuclear quadrupole
coupling interactions, large-amplitude motions, and inertial-frame reorientation
effects are resolved. (https://www.nist.gov/services-resources/software/jb95-spe
ctral-fitting-program)
• AABS is a program for the assignment and analysis of broadband spectra (Kisiel
et al. 2005).
• PGOPHER is a program used for the automatic assignment and fitting of spectra
(Western and Billinghurst 2019).
A collection of programs for various aspects of the rotational spectroscopy
problem are available free of charge from http://www.ifpan.edu.pl/~kisiel/prospe.
htm.
Appendix 1
Centrifugal distortion correction for a planar molecule.
From the experimental quartic centrifugal distortion constants, it is possible to
determine a set of five determinable combinations (Watson 1977)
T xx = − J − 2δ J = −D J + 2d 1 + 2d 2
(4.48a)
T yy = − J + 2δ J = −D J − 2d 1 + 2d 2
(4.48b)
T zz = − J − J K − K = −D J − D J K − D K
(4.48c)
T 1 = −3 J − J K = −3D J − D J K − 6d 2
(4.48d)
T 2 = −(B x + B y + B z )) J −
1
2
(B x + B y )) JK + (B x − B y )(δ J + δ K )
= −(B x + B y + B z )D J −
1
2
(B x + B y )D J K −
1
2
(B x − B y )d 1 − 6B z d 2
(4.48e)
where the notation of Watson (1977) has been used
T αα =
1
4
τ αααα
(4.49a)
T αβ =
1
4
τ ααββ
(4.49b)