List of alkali metal oxides

Alkali metal suboxides

• Hexarubidium monoxide (Rb6O)
• Nonarubidium dioxide (Rb9O2)
• Tricaesium monoxide (Cs3O) is a dark green solid.
• Tetracaesium monoxide (Cs4O)
• Heptacaesium monoxide (Cs7O)
• Tricaesium dioxide (Cs3O2)
• Heptacaesium dioxide (Cs7O2)
• Undecacaesium trioxide (Cs11O3)
• Undecacaesium monorubidium trioxide (Cs11RbO3)
• Undecacaesium dirubidium trioxide (Cs11Rb2O3)
• Undecacaesium trirubidium trioxide (Cs11Rb3O3)

Alkali metal oxides

• Lithium oxide (Li2O) is the lightest alkali metal oxide and a white solid. It melts at 1570 °C.
• Sodium oxide (Na2O) is a white solid that melts at 1132 °C and decomposes at 1950 °C. It is a component of glass.
• Potassium oxide (K2O) is a pale yellow solid that decomposes at 350 °C.
• Rubidium oxide (Rb2O) is a yellow solid that melts at 500 °C.
• Caesium oxide (Cs2O) is a yellow-orange solid that melts at 490 °C.

Alkali metal peroxides

• Lithium peroxide (Li2O2) is a white solid that melts at 195 °C. It reacts with carbon dioxide to form lithium carbonate and oxygen.
• Sodium peroxide (Na2O2) is a pale yellow solid that melts at 460 °C and decomposes at 657 °C.
• Potassium peroxide (K2O2) is a yellow solid that melts at 490 °C.
• Rubidium peroxide (Rb2O2) is produced when rubidium stands in air.
• Caesium peroxide (Cs2O2) is produced by the decomposition of caesium oxide above 400 °C.

Alkali metal sesquioxides

• Rubidium sesquioxide (Rb4O6) is a black solid.
• Caesium sesquioxide (Cs4O6) is a black solid.

Alkali metal superoxides

• Lithium superoxide (LiO2) has only been isolated in matrix isolation at 15 K.
• Sodium superoxide (NaO2) is a yellow-orange solid that melts at 551.7 °C. It is made by the high-pressure oxidation of sodium peroxide.
• Potassium superoxide (KO2) is a yellow solid that decomposes at 560 °C. It is used as a CO2 scrubber, H2O dehumidifier, and O2 generator in rebreathers, spacecraft, submarines, and spacesuit life support systems.
• Rubidium superoxide (RbO2) is produced when rubidium burns in air.
• Caesium superoxide (CsO2) is produced when caesium burns in air.

Alkali metal ozonides

• Lithium ozonide (LiO3) is a red solid which is produced from caesium ozonide via an ion-exchange process.
• Sodium ozonide (NaO3) is a red solid which is produced from caesium ozonide via an ion-exchange process.
• Potassium ozonide (KO3) is a dark red solid which is produced when potassium is burned in ozone or exposed to air for years.
• Rubidium ozonide (RbO3) is a dark red solid which is produced when rubidium is burned in ozone.
• Caesium ozonide (CsO3) is a dark red solid which is produced when caesium is burned in ozone.

References

References

1. (1998). "Synthesis and crystal structure determination of sodium ozonide". Chemical Communications.
2. [[F. Albert Cotton. F. A. Cotton]] and G. Wilkinson "Advanced Inorganic Chemistry", 5th edition (1988), p.462