Dianion diagnostics in DESIREE: High-sensitivity detection of C-n(2-) from a sputter ion sourceShow others and affiliations
Number of Authors: 172018 (English)In: Review of Scientific Instruments, ISSN 0034-6748, E-ISSN 1089-7623, Vol. 89, no 3, article id 033112Article in journal (Refereed) Published
Abstract [en]
A sputter ion source with a solid graphite target has been used to produce dianions with a focus on carbon cluster dianions, C-n(2-), with n = 7-24. Singly and doubly charged anions from the source were accelerated together to kinetic energies of 10 keV per atomic unit of charge and injected into one of the cryogenic (13 K) ion-beam storage rings of the Double ElectroStatic Ion Ring Experiment facility at Stockholm University. Spontaneous decay of internally hot C-n(2-) dianions injected into the ring yielded C-n(2-) anions with kinetic energies of 20 keV, which were counted with a microchannel plate detector. Mass spectra produced by scanning the magnetic field of a 90 degrees analyzing magnet on the ion injection line reflect the production of internally hot C-7(2-) - C-24(2-) dianions with lifetimes in the range of tens of microseconds to milliseconds. In spite of the high sensitivity of this method, no conclusive evidence of C-6(2-) was found while there was a clear C-7(2-) signal with the expected isotopic distribution. This is consistent with earlier experimental studies and with theoretical predictions. An upper limit is deduced for a C-6(2-) signal that is two orders-of-magnitude smaller than that for C-7(2-). In addition, CnO2- and CnCu2- dianions were detected.
Place, publisher, year, edition, pages
2018. Vol. 89, no 3, article id 033112
National Category
Physical Sciences
Research subject
Physics
Identifiers
URN: urn:nbn:se:su:diva-155975DOI: 10.1063/1.5010077ISI: 000428988300013PubMedID: 29604753Scopus ID: 2-s2.0-85044627193OAI: oai:DiVA.org:su-155975DiVA, id: diva2:1206011
2018-05-152018-05-152022-10-24Bibliographically approved
In thesis