RFM Isotopologues

15NOV17 - still needs updating for new HITRAN2016 isotopologues

The following is a list of all the isotopologues recognised by the RFM. This matches the list for HITRAN 2012 given on the HITRAN web-site (last checked 7 Jul 2017)

The table entries themselves are the commonly method of describing isotopes by the last digits of their atomic weights, eg the 'heavy hydrogen' version of H2O, 1H 16O 2H (actually the 4th most abundant isotope) is abbreviated to '162'.

Isotopes new for RFM v4.3
Isotopes not defined in HITRAN
ID Molecule Isotope Index
1 2 3 4 5 6 7 8 9 10 11
1 H2O 161 181 171 162 182 172
2 CO2 626 636 628 627 638 637 828 827 727 838 837
3 O3 666 668 686 667 676
4 N2O 446 456 546 448 447
5 CO 26 36 28 27 38 37
6 CH4 211 311 212 312
7 O2 66 68 67
8 NO 46 56 48
9 SO2 626 646 628 636
10 NO2 646
11 NH3 4111 5111
12 HNO3 146 156
13 OH 61 81 62
14 HF 19 29
15 HCl 15 17 25 27
16 HBr 19 11 29 21
17 HI 17 27
18 ClO 56 76
19 OCS 622 624 632 623 822 634
20 H2CO 126 136 128
21 HOCl 165 167
22 N2 44 45
23 HCN 124 134 125
24 CH3Cl 215 217
25 H2O2 1661
26 C2H2 1221 1231 1222
27 C2H6 1221 1231
28 PH3 1111
29 COF2 269 369
30 SF6 29
31 H2S 121 141 131
32 HCOOH 126
33 HO2 166
34 O 6
35 ClONO2 5646 7646
36 NO+ 46
37 HOBr 169 161
38 C2H4 221 231
39 CH3OH 2161
40 CH3Br 219 211
41 CH3CN 2124
42 CF4 29
43 C4H2 2211
44 HC3N 1224
45 H2 11 12
46 CS 12 24 32 23
47 SO3 26
Notes

  1. The RFM refers to each isotope by its HITRAN isotope index, as listed across the top of the table. These are in decreasing order of natural abundance.
  2. In Input files (inside .atm files, .gas files and entries in the driver table *GAS and *JAC sections) the isotopes is indicated by an entry in brackets following the molecule name, eg H2O(4) for isotope#4 of H2O
  3. In Output filenames, ie files created with isotopic Jacbians (JAC Flag), the isotope is indicated as an index following the character 'i' after the molecule name, eg h2oi4 for isotope#4 of H2O (this is different to the input because () characters in filenames can cause problems). The 'i' character itself is set by the PARAMETER CISO in subroutine jacnam.for, namgas_fnc.f90 in RFM v5).
  4. In HITRAN the line strengths are scaled by the abundance, which is convenient since it means a single VMR can be specified for all isotopes together
  5. The RFM also includes isotopes and complete molecules which are not (currently) part of the standard HITRAN dataset. Since the intention is to maintain the entire HITRAN dataset nomenclature as a subset of the RFM some of these assignments may change if they become included in HITRAN.
  6. The actual table used by the RFM is contained in subroutine gasiso.for (isolst_sub.f90 for RFM v5)