arsanes

https://doi.org/10.1351/goldbook.A00447
The saturated hydrides of tervalent arsenic, having the general formula AsnHn+2. Individual members having an unbranched arsenic chain are named arsane, diarsane, triarsane, etc. The name of a saturated hydride of arsenic where one or more arsenic atoms have bonding number 5 is formed by prefixing locants and λ5 symbols to the name of the corresponding arsane, e.g. H2AsAsHAsH2 triarsane, H4AsAsH3AsH4 1λ5,2λ5,3λ5-triarsane. Hydrocarbyl derivatives of AsH3 belong to the class arsines.
Source:
PAC, 1995, 67, 1307. 'Glossary of class names of organic compounds and reactivity intermediates based on structure (IUPAC Recommendations 1995)' on page 1319 (https://doi.org/10.1351/pac199567081307)