| Chemical formula | Synonyms | CAS number |
|---|---|---|
| OP | phosphorus monoxide | 14452-66-5 |
| OPb | lead monoxide | 1317-36-8 |
| OPd | palladium oxide | 1314-08-5 |
| OPr | praseodymium monoxide | 12035-81-3 |
| OPt | platinum monoxide | 12035-82-4 |
| ORb | rubidium monoxide | 12509-27-2 |
| ORb2 | dirubidium monoxide | 18088-11-4 |
| ORh | rhodium monoxide | 12137-18-7 |
| ORu | ruthenium monoxide | 12143-05-4 |
| OS | sulfur monoxide | 13827-32-2 |
| OSU | uranium monoxide monosulfide | 22201-28-1 |
| OS2 | disulfur monoxide | 20901-21-7 |
| SiO | silicon monoxide | 10097-28-6 |
| OSm | samarium monoxide | 12035-88-0 |
| OSn | tin monoxide | 21651-19-4 |
| OSr | strontium monoxide | 1314-11-0 |
| OSr2 | distrontium monoxide | 12035-89-1 |
| OTa | tantalum monoxide | 12035-90-4 |
| OTb | terbium monoxide | 12035-91-5 |
| OTb2 | diterbium monoxide | 62462-71-9 |
| OTe | tellurium monoxide | 13451-17-7 |
| OTh | thorium monoxide | 12035-93-7 |
| OTi | titanium monoxide | 12137-20-1 |
| OTl2 | dithallium oxide | 1314-12-1 |
| OTm | thulium monoxide | 12281-29-7 |
| OU | uranium monoxide | 12035-97-1 |
| OV | vanadium monoxide | 12035-98-2 |
| OW | tungsten oxide | 12035-99-3 |
| OY | yttrium monoxide | 12036-00-9 |
| OY2 | diyttrium monoxide | 12143-14-5 |
| OY3 | triyttrium monoxide | 161036-96-0 |
| OY5 | pentayttrium monoxide | 161036-97-1 |
| OYb | ytterbium monoxide | 25578-79-4 |
| OZr | zirconium monoxide | 12036-01-0 |
| O2P | phosphorus dioxide | 12164-97-5 |
| O2Pb | lead dioxide | 1309-60-0 |
| O2Pb2 | dilead dioxide | 35229-41-5 |
| O2Pr | praseodymium dioxide | 12036-05-4 |
| O2Pt | platinum dioxide | 1314-15-4 |
| O2Ru | ruthenium dioxide | 12036-10-1 |
| O2S | sulfur dioxide | 7446-09-5 |
| O2Se | selenium dioxide | 7446-08-4 |
| O2Si | silicon dioxide | 60676-86-0 |
| O2Si | silicon oxide | 14464-46-1 |
| O2Si | silicon oxide | 14808-60-7 |
| O2Si | silicon oxide | 99493-55-7 |
| O2Sn | stannic oxide | 18282-10-5 |
| O2Sn2 | ditin dioxide | 12534-17-7 |
| O2Ta | tantalum dioxide | 12036-14-5 |
| O2Tb2 | diterbium dioxide | 62462-78-6 |
| O2Te | tellurium dioxide | 59863-17-1 |
| O2Th | thorium dioxide | 1314-20-1 |
| O2Ti | titanium dioxide | 13463-67-7 |
| O2Ti | titanium oxide | 1309-63-3 |
| O2Ti | titanium oxide | 1317-70-0 |
| O2U | uranium dioxide | 1344-57-6 |
| O2V | vanadium dioxide | 12036-21-4 |
| O2W | tungsten dioxide | 12036-22-5 |
| O2Zr | zirconium dioxide | 1314-23-4 |
| O3Os | osmium trioxide | 12036-24-7 |
| O3P2 | diphosphorus trioxide | 1314-24-5 |
| O3PbSi | lead silicate | 10099-76-0 |
| O3Pb3 | trilead trioxide | 12359-22-7 |
| O3Re | rhenium trioxide | 1314-28-9 |
| O3Ru | ruthenium trioxide | 12036-36-1 |
| O3S | sulfur trioxide | 7446-11-9 |
| O3Sb2 | antimony trioxide | 1309-64-4 |
| O3Se | selenium trioxide | 13768-86-0 |
| O3Sn3 | tritin trioxide | 12534-28-0 |
| O3SrW | strontium trioxotungstate | 12143-37-2 |
| O3Ti | titanium oxide peroxide | 1344-55-4 |
| O3Ti2 | dititanium trioxide | 1344-54-3 |
| O3U | uranium trioxide | 1344-58-7 |
| O3W | tungsten trioxide | 1314-35-8 |
| O3Y2 | yttrium oxide | 1314-36-9 |
| O4Os | osmium tetraoxide | 20816-12-0 |
| O4P2 | diphosphorus tetraoxide | 12137-38-1 |
| O4PbS | lead sulfate | 7446-14-2 |
| O4Pb2Si | lead silicate | 13566-17-1 |
| O4Pb4 | tetralead tetraoxide | 36502-09-7 |
| O4Ru | ruthenium tetraoxide | 20427-56-9 |
| O4STl2 | dithallium sulfate | 7446-18-6 |
| O4SZn | zinc sulfate | 7733-02-0 |
| O4SiZr | zirconium silicate | 10101-52-7 |
| O4SnW | tin monotungstate | 14553-36-7 |
| O4Sn4 | tin oxide | 12534-33-7 |
| O4SrW | strontium tetraoxotungstate | 13451-05-3 |
| O4Ti2 | dititanium tetraoxide | 99803-43-7 |
| O5P2 | diphosphorus pentoxide | 1314-56-3 |
| O5Ti3 | titanium oxide | 12065-65-5 |
| O6P4 | phosphorus oxide | 12440-00-5 |
| O6P4 | tetraphosphorus hexaoxide | 10248-58-5 |
| O6Sb4 | tetraantimony hexaoxide | 72926-13-7 |
| O6W2 | ditungsten hexaoxide | 12165-16-1 |
| O7P4 | tetraphosphorus heptaoxide | 12065-80-4 |
| O7Re2 | dirhenium heptaoxide | 1314-68-7 |
| O7Ti4 | titanium oxide | 12143-55-4 |
| O8P4 | tetraphosphorus octoxide | 12037-06-8 |
| O8U3 | triuranium octoxide | 1344-59-8 |
| O8V4 | tetravanadium octaoxide | 12503-87-6 |
| O8W3 | tungsten oxide | 12165-25-2 |
| O9P4 | tetraphosphorus nonoxide | 12037-11-5 |
| O9W3 | tritungsten nonaoxide | 12165-37-6 |
| O10P4 | tetraphosphorus decaoxide | 16752-60-6 |
| O10V4 | tetravanadium decaoxide | 12503-98-9 |
| O12W4 | tetratungsten dodecaoxide | 12165-45-6 |