This is subvolume D (appearing in three parts, D1, D2, and D3) of the Landolt-Börnstein Volume II/29 “Molecular Constants Mostly from Microwave, Molecular Beam, and Sub-Doppler Laser Spectroscopy”, which is planned to appear as a series A, B, C, D1, D2, D3 for the diamagnetic, and E for the paramagnetic diatomic and paramagnetic polyatomic species, respectively. Like in the preceding volumes II/24 and II/19, which have appeared in the years around 1999 and 1992, respectively, the diamagnetic substances are arranged in the manner suggested by Hill (“Hill's system”, 1900), meaning an almost strict alphabetical order; details are given in the General Introduction on the following pages. The ionic species are included in the alphabetical arrangement of the neutral ones in each table. In the preface to the previous volume II/24 we had noted: It is somewhat surprising that the trend of reducing spectroscopic activities in universities and other research institutes has not led to a lower production rate of pertinent molecular literature data during the last say ten years. It seems that the opposite is true. The number of studies of Van der Waals complexes is still increasing, and naturally also their complexity. Similarly, the “normal” molecules studied under high-resolution conditions became more complicated and flexible, and interesting effects like inner hydrogen bonding have been investigated. The number of figures used to illustrate the molecular conformational structures is, therefore, also larger than in the foregoing volumes.

Table of Contents:
1 General Introduction.- 2 Asymmetric Top Molecules: Introduction.- 1 AgHO Silver hydroxide.- 2 AlHS Aluminum hydrogen sulfide.- 3 ArClHNe Argon - hydrogen chloride - neon (1/1/1).- 4 ArH2S Argon - hydrogen sulfide (1/1).- 5 ArH3 + Argon - protonated dihydrogen (1/1).- 6 ArH3N Argon - ammonia (1/1).- 7 ArH4O2 Argon - water (1/2).- 8 ArH4S2 Argon - hydrogen sulfide (1/2).- 9 ArN2NeO Argon - dinitrogen monoxide - neon (1/1/1).- 10 ArN2O Argon - dinitrogen monoxide (1/1).- 11 ArNe2 Argon - neon (1/2).- 12 ArO2S Argon - sulfur dioxide (1/1).- 13 Ar2BrH Argon - hydrogen bromide (2/1).- 14 Ar2ClH Argon - hydrogen chloride (2/1).- 15 Ar2FH Argon - hydrogen fluoride (2/1).- 16 Ar2H2O Argon - water (2/1).- 17 Ar2H2S Argon - hydrogen sulfide (2/1).- 18 Ar2H3N Argon - ammonia (2/1).- 19 Ar2N2O Dinitrogen monoxide - argon (1/2).- 20 Ar2Ne Argon - neon (2/1).- 21 Ar2Ne2 Argon - neon (2/2).- 22 BFH2O2 Fluorodihydroxyborane.- 23 BF2HO Difluorohydroxyborane.- 24 BF3O2S Trifluoroborane - sulfur dioxide(1/1).- 25 BrClH2O Bromine chloride - water (1/1).- 26 BrHO Hypobromous acid.- 27 BrHSi Bromosilylene.- 28 BrH5O2 Hydrogen bromide - water (1/2).- 29 BrNO Nitrosyl bromide.- 30 Br2H2O Dibromine - water (1/1).- 31 Br2H2S Dibromine - hydrogen sulfide (1/1).- 32 Br2O Dibromine monoxide.- 33 CArNeO2 Carbon dioxide - argon - neon (1/1/1).- 34 CArO Carbon monoxide - argon (1/1).- 35 CArOS Carbonyl sulfide - argon (1/1).- 36 CAr2OS Carbonyl sulfide - argon (1/2).- 37 CAr2O2 Carbon dioxide - argon (1/2).- 38 CBrClF2 Bromochlorodifluoromethane.- 39 CClF2N Chlorocarbonimidic difluoride.- 40 CCl2 Dichloromethylene.- 41 CCl2F2 Dichlorodifluoromethane.- 42 CCl3NO2 Trichloronitromethane.- 43 CF2 Difluoromethylene.- 44 CF2Se Carbonoselenoic difluoride.- 45 CF3NO2 Trifluoronitromethane.- 46 CHBr Bromomethylene.- 47 CHBrClF Bromochlorofluoromethane.- 48 CHBrF2 Bromodifluoromethane.- 49 CHCl Chloromethylene.- 50 CHClFI Chlorofluoroiodomethane.- 51 CHClF2 Chlorodifluoromethane.- 52 CHCl2F Dichlorofluoromethane.- 53 CHF Fluoromethylene.- 54 CHNS Hydrogen isothiocyanate.- 55 CHNSi Cyanosilylene.- 56 CHNSi Isocyanosilylene.- 57 CH2ArClF Chlorofluoromethane - argon (1/1).- 58 CH2ArF2 Difluoromethane - argon (1/1).- 59 CH2BrF Bromofluoromethane.- 60 CH2ClFO Formaldehyde - chlorine fluoride (1/1).- 61 CH2Cl2 Dichloromethane.- 62 CH2F2 Difluoromethane.- 63 CH2F2Kr Difluoromethane - krypton (1/1).- 64 CH2F2Xe Difluoromethane - xenon (1/1).- 65 CH2F3NS 1,1,1-Trifluoromethanesulfenamide.- 66 CH2I2 Diiodomethane.- 67 CH2NP Cyanophosphine.- 68 CH2N2 Cyanamide.- 69 CH2N2 Methanediimine.- 70 CH2O Formaldehyde.- 71 CH2OS Carbon monoxide - hydrogen sulfide (1/1).- 72 CH2O2 Formic acid.- 73 CH2O2S Carbonyl sulfide - water (1/1).- 74 CH2O3 Carbon dioxide - water (1/1).- 75 CH2S Thioformaldehyde.- 76 CH3FHe Fluoromethane - helium (1/1).- 77 CH3FO2S Methanesulfonyl fluoride.- 78 CH3F2OP Methylphosphonic difluoride.- 79 CH3NO Formamide.- 80 CH3NO2 Nitrous acid methyl ester.- 81 CH3O+ Hydroxymethylium.- 82 CH3P Methylenephosphine.- 83 CH4F2NPS Methylphosphoramidothioic difluoride.- 84 CH4F2O Difluoromethane - water (1/1).- 85 CH4N2O Urea.- 86 CH4N2O Hydrazinecarboxaldehyde.- 87 CH4N2S Thiourea.- 88 CH4O Methanol.- 89 CH4O3 Methane - ozone (1/1).- 90 CH4O3 Formic acid - water (1/1).- 91 CH4S Methanethiol.- 92 CH4Si Methylenesilane.- 93 CH5ClO Methanol - hydrogen chloride (1/1).- 94 CH5N Methylamine.- 95 CH5NO2 Formamide - water (1/1).- 96 CH6O2 Methanol - water (1/1).- 97 CH6O4 Formic acid - water (1/2).- 98 CH7NO3 Formamide - water (1/2).- 99 CHeOS Carbonyl sulfide - helium (1/1).- 100 CHeO2 Carbon dioxide - helium (1/1).- 101 CHe2OS Carbonyl sulfide - helium (1/2).- 102 CHe3OS Carbonyl sulfide - helium (1/3).- 103 CHe4OS Carbonyl sulfide - helium (1/4).- 104 CHe5OS Carbonyl sulfide - helium (1/5).- 105 CHe6OS Carbonyl sulfide - helium (1/6).- 106 CHe7OS Carbonyl sulfide - helium (1/7).- 107 CHe8OS Carbonyl sulfide - helium (1/8).- 108 CKrO Carbon monoxide - krypton (1/1).- 109 CN2O Carbon monoxide - dinitrogen (1/1).- 110 CN2O2 Carbon monoxide - dinitrogen monoxide (1/1).- 111 CN2O2S Carbonyl sulfide - dinitrogen monoxide (1/1).- 112 CN2O3 Carbon dioxide - dinitrogen monoxide (1/1).- 113 CNeO Carbon monoxide - neon (1/1).- 114 CNeO2 Carbon dioxide - neon (1/1).- 115 CNe2OS Carbonyl sulfide - neon (1/2).- 116 COXe Carbon monoxide - xenon (1/1).- 117 CO2S3 Carbon disulfide - sulfur dioxide (1/1).- 118 CO3S2 Carbonyl sulfide - sulfur dioxide (1/1).- 119 C2HCl3 Trichloroethene.- 120 C2HF3 1,1,2-Trifluoroethene.- 121 C2HF3OS Carbonyl sulfide - trifluoromethane (1/1).- 122 C2HF3O2 Trifluoroacetic acid.- 123 C2HF5 Pentafluoroethane.- 124 C2H2Ar Ethyne - argon (1/1).- 125 C2H2ArF2 1,1-Difluoroethene - argon (1/1).- 126 C2H2ArO Ethenone - argon (1/1).- 127 C2H2Ar2O Ethenone - argon (1/2).- 128 C2H2BrClO Bromoacetyl chloride.- 129 C2H2BrF 1-Bromo-1-fluoroethene.- 130 C2H2BrF (1Z)-1-Bromo-2-fluoroethene.- 131 C2H2BrF (1E)-1-Bromo-2-fluoroethene.- 132 C2H2Br2 Ethyne - dibromine (1/1).- 133 C2H2ClF (1Z)-1-Chloro-2-fluoroethene.- 134 C2H2ClF (1E)-1-Chloro-2-fluoroethene.- 135 C2H2ClF3 1-Chloro-1,1,2-trifluoroethane.- 136 C2H2ClI Ethyne - iodine chloride (1/1).- 137 C2H2Cl2 1,1-Dichloroethene.- 138 C2H2Cl2 (1E)-1,2-Dichloroethene.- 139 C2H2F2 (1Z)-1,2-Difluoroethene.- 140 C2H2F2 (1E)-1,2-Difluoroethene.- 141 C2H2F2Ne 1,1-Difluoroethene - neon (1/1).- 142 C2H2F4 1,1,1,2-Tetrafluoroethane.- 143 C2H2F4 1,1,2,2-Tetrafluoroethane.- 144 C2H2F4 1,1,2-Trifluoroethene - hydrogen fluoride (1/1).- 145 C2H2F4O 1,1’-Oxybis[difluoromethane].- 146 C2H2N2O Carbonocyanidic amide.- 147 C2H2N2O 1,2,5-Oxadiazole.- 148 C2H2N2O 1,3,4-Oxadiazole.- 149 C2H2N2O Ethyne - dinitrogen monoxide (1/1).- 150 C2H2N2S 1,2,5-Thiadiazole.- 151 C2H2N2S 1,3,4-Thiadiazole.- 152 C2H2N2Se 1,2,5-Selenadiazole.- 153 C2H2O Ethenone.- 154 C2H2O2 Ethanedial (glyoxal).- 155 C2H2O3 2-Oxoacetic acid.- 156 C2H2O4 Ethanedioic acid.- 157 C2H2Si Ethenylidenesilylene.- 158 C2H3ArN Isocyanomethane - argon (1/1).-159 C2H3Br Bromoethene.- 160 C2H3Br Ethyne - hydrogen bromide (1/1).- 161 C2H3Cl Chloroethene.- 162 C2H3ClF2 1-Chloro-1,1-difluroethane.- 163 C2H3ClF2 Fluoroethene - chlorine fluoride (1/1).- 164 C2H3Cl2NO (E)-Dichloroacetaldehyde oxime.- 165 C2H3F Fluoroethene.- 166 C2H3FOS Fluoromethane - carbonyl sulfide (1/1).- 167 C2H3F3O3 2,2,2-Trifluoroacetic acid - water (1/1).- 168 C2H3I Iodoethene.- 169 C2H4 Ethene.- 170 C2H4Ar Ethene - argon (1/1).- 171 C2H4ArF2 1,2-Difluoroethane - argon (1/1).- 172 C2H4ArF2 1,1-Difluoroethane - argon (1/1).- 173 C2H4ArO Acetaldehyde - argon (1/1).- 174 C2H4ArO Oxirane - argon (1/1).- 175 C2H4BrF 1-Bromo-1-fluoroethane.- 176 C2H4BrF Fluoroethene - hydrogen bromide (1/1).- 177 C2H4Br2 Ethene - dibromine (1/1).- 178 C2H4ClI Ethene - iodine chloride (1/1).- 179 C2H4ClNO (1E)-Chloroacetaldehyde oxime.- 180 C2H4ClNO 2-Chloroacetamide.- 181 C2H4Cl2 1,1-Dichloroethane.- 182 C2H4Cl2 1,2-Dichloroethane.- 183 C2H4F2 1,2-Difluoroethane.- 184 C2H4F2 Fluoroethene - hydrogen fluoride (1/1).- 185 C2H4F2O Oxirane - difluorine (1/1).- 186 C2H4F4 Difluoromethane dimer.- 187 C2H4F4 Fluoromethane - trifluoromethane (1/1).- 188 C2H4KrO Acetaldehyde - krypton (1/1).- 189 C2H4KrO Oxirane - krypton (1/1).- 190 C2H4Ne Ethene - neon (1/1).- 191 C2H4O Acetaldehyde.- 192 C2H4O Oxirane.- 193 C2H4OS Methane - carbonyl sulfide (1/1).- 194 C2H4OXe Oxirane - xenon (1/1).- 195 C2H4O2 Acetic acid.- 196 C2H4O2 Formic acid methyl ester.- 197 C2H4O2 2-Hydroxyacetaldehyde.- 198 C2H4O3 2-Hydroxyacetic acid.- 199 C2H4O3 Methanol - carbon dioxide (1/1).- 200 C2H4S Thiirane.- 201 C2H4Se Etheneselenol.- 202 C2H5As Ethenylarsine.- 203 C2H5Br Ethene - hydrogen bromide (1/1).- 204 C2H5FO 2-Fluoroethanol.- 205 C2H5FS Thiirane-hydrogen fluoride (1/1).- 206 C2H5F2OP Ethylphosphonic difluoride.- 207 C2H5F2P Ethylphosphorous difluoride.- 208 C2H5F3O4 2,2,2-Trifluoroacetic acid-water (1/2).- 209 C2H5N Aziridine.- 210 C2H5NO N-Methylformamide.- 211 C2H5NO Acetamide.- 212 C2H5NO (1E)-Acetaldehyde oxime.- 213 C2H5NO (1Z)-Acetaldehyde oxime.- 214 C2H5NO2 Glycine.- 215 C2H5NO2 Nitrous acid ethyl ester.- 216 C2H5NO2 Carbamic acid methyl ester.- 217 C2H5NO2 2-Hydroxyacetamide.- 218 C2H5Sb Ethenylstibine.- 219 C2H6ArF2Si Difluoromethylsilane - argon (1/1).- 220 C2H6ArO Ethanol - argon (1/1).- 221 C2H6ArO 1,1’-Oxybis[methane] - argon (1/1).- 222 C2H6F2Si Difluorodimethylsilane.- 223 C2H6KrO 1,1’-Oxybis[methane] - krypton (1/1).- 224 C2H6NeO 1,1’-Oxybis[methane] - neon (1/1).- 225 C2H6NeS 1,1’-Thiobis[methane] - neon (1/1).- 226 C2H6O Ethanol.- 227 C2H6O 1,1’-Oxybis[methane].- 228 C2H6OXe 1,1’-Oxybis[methane] - xenon (1/1).- 229 C2H6O2 1,2-Ethanediol.- 230 C2H6O2 Methanol - formaldehyde (1/1).- 231 C2H6O2 Oxirane - water (1/1).- 232 C2H6O3 2-Hydroxyacetaldehyde - water (1/1).- 233 C2H6O5 Formic acid - water (2/1).- 234 C2H6S 1,1’-Thiobis[methane].- 235 C2H6S Ethene - hydrogen sulfide (1/1).- 236 C2H6S2 1,2-Ethanedithiol.- 237 C2H6Se2 Dimethyl diselenide.- 238 C2H7ArNO 2-Aminoethanol - argon (1/1).- 239 C2H7ClO 1,1’-Oxybis[methane] - hydrogen chloride (1/1).- 240 C2H7ClSi Chlorodimethylsilane.- 241 C2H7FO 1,1’-Oxybis[methane] - hydrogen fluoride (1/1).- 242 C2H7F3O5 2,2,2-Trifluoroacetic acid - water (1/3).- 243 C2H7NO 2-Aminoethanol.- 244 C2H8ArSi Dimethylsilane - argon (1/1).- 245 C2H8O2 Methanol dimer.- 246 C2H8Si Ethylsilane.- 247 C2H8Si Dimethylsilane.- 248 C2H9NO2 2-Aminoethanol - water (1/1).- 249 C2N2O5 Carbon dioxide - dinitrogen monoxide (2/1).- 250 C2N2S Sulfur dicyanide.- 251 C2OS3 Carbon disulfide - carbonyl sulfide (1/1).- 252 C2O2S Carbon monoxide - carbonyl sulfide (1/1).- 253 C2O2S2 Carbonyl sulfide dimer.- 254 C2O3 Carbon dioxide - carbon monoxide (1/1).