Contents 
II/20 Molecular Constants 

Subvolume B5

:Linear Triatomic Molecules CS2 (SCS), CS2+ (SCS+), CS2++(SCS++), CSe2 (SeCSe), C2N (CCN), C2N (CNC), C2N+ (CCN+), C2N+ (CNC+) Introduction ..................................................................... IX

(Specific comments related to some of the molecules considered in the previous subvolumes II/20B1...4
are retained in the present introduction due to their possible general applicability)

I 
Energy level designations..................................................IX

II 
Effective Hamiltonians..................................................... X

II.1 
Energy matrix............................................................ X

II.1.1 
Diagonal elements........................................................ X

II.1.2 
Off-diagonal elements.................................................... XII

II.2 
Energy expressions referred to the ground state................................ XII

II.2.1 
Vibrational states....................................................... XIII

II.2.2 
Rotational states ....................................................... XIII

II.3 
Conversion table for energy-related units and selected fundamental constants....... XIV

III 
Formulas for determining rotational constants................................. XV

III.1 
Effective parameters...................................................... XV

III.2 
Band center and band origin.............................................. XVI

III.3 
Comments on BHO (HBO) (see Chap. 6 of subvolume II/20B1)..................XVII

III.4 
Some specifics related to COS (OCS) (see Chap. 38 of subvolume II/20B1)....... XVIII

III.4.1 
Diagonalizing the energy matrix..........................................XVIII

III.4.2 
Effective molecular parameters........................................... XVIII

III.4.3 
Unperturbed vibrational states............................................. XIX

III.4.4 
Effects of perturbations.................................................. XIX




III.5 Quadrupole coupling.................................................... XXI
IV Potential energy function (PEF)............................................ XXI

IV.1 PEF expanded as a Taylor series........................................... XXI

IV.2 Curvilinear valence coordinates and Morse functions...........................XXII

IV.3 Dimensionless normal coordinates.........................................XXII

IV.4 Specific forms of the PEF................................................XXII
V Dipole moment........................................................XXIV

V.1 General equations......................................................XXIV

V.2 Specifics related to COS (OCS) (see Chap. 38 of subvolume II/20B1)............ XXV
VI Intensities........................................................... XXVII

VI.1 Intensities of spectral lines.............................................. XXVII

VI.2 Integrated absorption intensities......................................... XXVII

VI.3 Total internal partition sum..............................................XXIX

VI.4 F-factors (Herman-Wallis factors)......................................... XXIX

VI.5 Intensity expressions................................................... XXX

VI.6 Intensity units and conversion table........................................XXXI

VI.7 Line profiles....................................................... XXXVIII

VI.7.1 Lorentz profile..................................................... XXXVIII

VI.7.2 Doppler profile..................................................... XXXVIII

VI.7.3 Voigt profile....................................................... XXXVIII

VI.7.4 Galatry profile...................................................... XXXIX

VI.8 Miscellaneous topics................................................. XXXIX

VI.8.1 Some definitions related to collisions.................................... XXXIX

VI.8.2 Foreign gas broadening............................................... XXXIX

VI.8.3 
Line coupling........................................................... XL


VIII Contents 
VI.8.4 Temperature dependence of broadening...................................... XL

VI.9 Einstein coefficient of spontaneous emission ................................. XLI

VI.10 Rotational state transfer.................................................. XLI
VII Renner-Teller effect (some aspects) ........................................XLII
VIII Some functional relations specially applicable to the molecular constants of CO2 ... XLIV

VIII.1 Designations of the energy levels of CO2................................... XLIV

VIII.2 Resonances in CO2..................................................... XLIV

VIII.3.1 Potential-energy function (PEF) ........................................XLVIII

VIII.3.2 Interaction potential...................................................XLVIII

VIII.4.1 Dipole moment.......................................................XLVIII

VIII.4.2 Transition dipole moment ............................................... XLIX

VIII.5 HITELOR (High Temperature Low Resolution data base)...................... XLIX

VIII.6 Line mixing .......................................................... XLIX

VIII.7 Several functional relations in which effects of collisions are included ............... LI

VIII.7.1 Collisional broadening..................................................... LI

VIII.7.2 Binary absorption coefficient................................................ LI

VIII.7.3 Normalized absorption coefficient............................................ LI

VIII.7.4 Collision induced contribution in the band intensity............................. LII

VIII.8 Self broadening and its temperature dependence ............................... LII

VIII.9 Foreign gas broadening................................................... LII

VIII.10 Transmittance at the center of a spectral line................................... LII

VIII.11 Line mixing (temperature and pressure dependence) ...........................LIII

VIII.11.1 Temperature dependence of line mixing......................................LIII

VIII.11.2 Pressure dependence of line mixing .........................................LIII

VIII.12 Some formulas for the absorption coefficient k(.) .............................LIII

VIII.12.1 Impact approximation ....................................................LIII

VIII.12.2 First order theory of Rosenkranz........................................... LIV

VIII.13 CO2 laser wave guide amplification and power saturation....................... LIV
IX Some symbolism appearing in N2O data...................................... LV
X Some symbolism appearing in CO2+, CFeO, CFeO, CNN, CNO and CNO data.... LVIII

X.1 Aspects of some notations in polyatomic molecules........................... LVIII


2+
X.2 ................................................................ LVIII

X.3 CFeO for which the electronic ground state is 3S ............................ LXIII

X.4 CNN (NCN).......................................................... LXIII
XI Some functional relations for CS2, CSe2 and C2N molecules and ions ............. LXVI

XI.1 CS2 (SCS) and CSe2 (SeCSe)............................................. LXVI

XI.2 C2N (CCN) and C2N (CNC) ............................................. LXVI
XII List of symbols....................................................... LXXII

Data 
1 BClH+ (HBCl+) ... 39 COSe (OCSe) ................................. see subvolume II/20B1

40.1 12C16O16O (16O12C16O) ........................................ see subvolume II/20B2a

40.2 ... 40.14 12C16O17O (16O12C17O) ... 14C18O18O (18O14C18O) ............. see subvolume II/20B2

41.1 ... 41.12 14N14N16O (14N14N16O)... 15N15N18O (15N15N18O) .............. see subvolume II/20B3
42 COO+ (OCO+) ... 50 CNO (NCO) ................................. see subvolume II/20B4

51 CS2 (SCS), ... 58 C2N+ (CNC+) (survey).............................................. 1

References ..................................................................... . 2 17

Survey of content 

II/20 Molecular Constants 
CS2 (SCS), ... C2N+ (CNC+) Subvolume B5 
Introduction List of Symbols Table References 


