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Najeeb PK, Stockett MH, Anderson EK, Kristiansson MK, Reinhed P, Simonsson A, Rosén S, Thomas RD, Chartkunchand KC, Gnaser H, Golser R, Hanstorp D, Larson Å, Cederquist H, Schmidt HT, Zettergren H. Stability and Cooling of the C_{7}^{2-} Dianion. PHYSICAL REVIEW LETTERS 2023; 131:113003. [PMID: 37774298 DOI: 10.1103/physrevlett.131.113003] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Subscribe] [Scholar Register] [Received: 03/07/2023] [Revised: 06/26/2023] [Accepted: 08/12/2023] [Indexed: 10/01/2023]
Abstract
We have studied the stability of the smallest long-lived all carbon molecular dianion (C_{7}^{2-}) in new time domains and with a single ion at a time using a cryogenic electrostatic ion-beam storage ring. We observe spontaneous electron emission from internally excited dianions on millisecond timescales and monitor the survival of single colder C_{7}^{2-} molecules on much longer timescales. We find that their intrinsic lifetime exceeds several minutes-6 orders of magnitude longer than established from earlier experiments on C_{7}^{2-}. This is consistent with our calculations of vertical electron detachment energies predicting one inherently stable isomer and one isomer which is stable or effectively stable behind a large Coulomb barrier for C_{7}^{2-}→C_{7}^{-}+e^{-} separation.
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Affiliation(s)
- P K Najeeb
- Department of Physics, Stockholm University, AlbaNova, Stockholm SE-106 91, Sweden
| | - M H Stockett
- Department of Physics, Stockholm University, AlbaNova, Stockholm SE-106 91, Sweden
| | - E K Anderson
- Department of Physics, Stockholm University, AlbaNova, Stockholm SE-106 91, Sweden
| | - M K Kristiansson
- Department of Physics, Stockholm University, AlbaNova, Stockholm SE-106 91, Sweden
| | - P Reinhed
- Department of Physics, Stockholm University, AlbaNova, Stockholm SE-106 91, Sweden
| | - A Simonsson
- Department of Physics, Stockholm University, AlbaNova, Stockholm SE-106 91, Sweden
| | - S Rosén
- Department of Physics, Stockholm University, AlbaNova, Stockholm SE-106 91, Sweden
| | - R D Thomas
- Department of Physics, Stockholm University, AlbaNova, Stockholm SE-106 91, Sweden
| | - K C Chartkunchand
- AMO Physics Laboratory, RIKEN Advanced Science Institute, Saitama 351-0198, Japan
| | - H Gnaser
- Institute for Isotope Physics, University of Vienna, Vienna A-1090, Austria
| | - R Golser
- Institute for Isotope Physics, University of Vienna, Vienna A-1090, Austria
| | - D Hanstorp
- Department of Physics, University of Gothenburg, SE-412 96 Gothenburg, Sweden
| | - Å Larson
- Department of Physics, Stockholm University, AlbaNova, Stockholm SE-106 91, Sweden
| | - H Cederquist
- Department of Physics, Stockholm University, AlbaNova, Stockholm SE-106 91, Sweden
| | - H T Schmidt
- Department of Physics, Stockholm University, AlbaNova, Stockholm SE-106 91, Sweden
| | - H Zettergren
- Department of Physics, Stockholm University, AlbaNova, Stockholm SE-106 91, Sweden
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Chartkunchand KC, Stockett MH, Anderson EK, Eklund G, Kristiansson MK, Kamińska M, de Ruette N, Blom M, Björkhage M, Källberg A, Löfgren P, Reinhed P, Rosén S, Simonsson A, Zettergren H, Schmidt HT, Cederquist H. Dianion diagnostics in DESIREE: High-sensitivity detection of C n2- from a sputter ion source. THE REVIEW OF SCIENTIFIC INSTRUMENTS 2018; 89:033112. [PMID: 29604753 DOI: 10.1063/1.5010077] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 06/08/2023]
Abstract
A sputter ion source with a solid graphite target has been used to produce dianions with a focus on carbon cluster dianions, Cn2-, 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 Cn2- dianions injected into the ring yielded Cn- 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° analyzing magnet on the ion injection line reflect the production of internally hot C72- - C242- 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 C62- was found while there was a clear C72- signal with the expected isotopic distribution. This is consistent with earlier experimental studies and with theoretical predictions. An upper limit is deduced for a C62- signal that is two orders-of-magnitude smaller than that for C72-. In addition, CnO2- and CnCu2- dianions were detected.
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Affiliation(s)
- K C Chartkunchand
- Department of Physics, Stockholm University, AlbaNova, SE-106 91 Stockholm, Sweden
| | - M H Stockett
- Department of Physics, Stockholm University, AlbaNova, SE-106 91 Stockholm, Sweden
| | - E K Anderson
- Department of Physics, Stockholm University, AlbaNova, SE-106 91 Stockholm, Sweden
| | - G Eklund
- Department of Physics, Stockholm University, AlbaNova, SE-106 91 Stockholm, Sweden
| | - M K Kristiansson
- Department of Physics, Stockholm University, AlbaNova, SE-106 91 Stockholm, Sweden
| | - M Kamińska
- Department of Physics, Stockholm University, AlbaNova, SE-106 91 Stockholm, Sweden
| | - N de Ruette
- Department of Physics, Stockholm University, AlbaNova, SE-106 91 Stockholm, Sweden
| | - M Blom
- Department of Physics, Stockholm University, AlbaNova, SE-106 91 Stockholm, Sweden
| | - M Björkhage
- Department of Physics, Stockholm University, AlbaNova, SE-106 91 Stockholm, Sweden
| | - A Källberg
- Department of Physics, Stockholm University, AlbaNova, SE-106 91 Stockholm, Sweden
| | - P Löfgren
- Department of Physics, Stockholm University, AlbaNova, SE-106 91 Stockholm, Sweden
| | - P Reinhed
- Department of Physics, Stockholm University, AlbaNova, SE-106 91 Stockholm, Sweden
| | - S Rosén
- Department of Physics, Stockholm University, AlbaNova, SE-106 91 Stockholm, Sweden
| | - A Simonsson
- Department of Physics, Stockholm University, AlbaNova, SE-106 91 Stockholm, Sweden
| | - H Zettergren
- Department of Physics, Stockholm University, AlbaNova, SE-106 91 Stockholm, Sweden
| | - H T Schmidt
- Department of Physics, Stockholm University, AlbaNova, SE-106 91 Stockholm, Sweden
| | - H Cederquist
- Department of Physics, Stockholm University, AlbaNova, SE-106 91 Stockholm, Sweden
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Affiliation(s)
- Xue-Bin Wang
- Department of Physics, Washington State University, Richland, Washington 99354, and Chemical and Materials Sciences Division, Pacific Northwest National Laboratory, Richland, Washington 99352;
| | - Lai-Sheng Wang
- Department of Physics, Washington State University, Richland, Washington 99354, and Chemical and Materials Sciences Division, Pacific Northwest National Laboratory, Richland, Washington 99352;
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Franzreb K, Williams P. Small gas-phase dianions produced by sputtering and gas flooding. J Chem Phys 2005; 123:224312. [PMID: 16375481 DOI: 10.1063/1.2136154] [Citation(s) in RCA: 13] [Impact Index Per Article: 0.7] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/22/2023] Open
Abstract
We have extended our previous experiment [Schauer et al., Phys. Rev. Lett. 65, 625 (1990)] where we had produced small gas-phase dianion clusters of C(n) (2-)(n > or =7) by means of sputtering a graphite surface by Cs(+) ion bombardment. Our detection sensitivity for small C(n) (2-) could now be increased by a factor of about 50 for odd n. Nevertheless, a search for the elusive pentamer dianion of C(5) (2-) was not successful. As an upper limit, the sputtered flux of C(5) (2-) must be at least a factor of 5000 lower than that of C(7) (2-), provided that the lifetime of C(5) (2-) is sufficiently long to allow its detection by mass spectrometry. When oxygen gas (flooding with either O(2) or with N(2)O) was supplied to the Cs(+)-bombarded graphite surface, small dianions of OC(n) (2-)(5< or =n < or =14) and O(2)C(7) (2-) were observed in addition to C(n) (2-)(n > or =7). Similarly, Cs(+) sputtering of graphite with simultaneous SF(6) gas flooding produced SC(n) (2-)(6< or =n< or =18). Mixed nitrogen-carbon or fluorine-carbon dianion clusters could not be observed by these means. Attempts to detect mixed metal-fluoride dianions for SF(6) gas flooding of various Cs(+)-bombarded metal surfaces were successful for the case of Zr, where metastable ZrF(6) (2-) was observed. Cs(+) bombardment of a silicon carbide (SiC) wafer produced SiC(n) (2-) (n=6,8,10). When oxygen gas was supplied to the Cs(+)-bombarded SiC surface, small dianions of SiOC(n) (2-) (n=4,6,8) and of SiO(2)C(n) (2-) (n=4,6) as well as a heavier unidentified dianion (at mz=98.5) were observed. For toluene (C(7)H(8)) vapor flooding of a Cs(+)-bombarded graphite surface, several hydrocarbon dianion clusters of C(n)H(m) (2-)(n> or =7) were produced in addition to C(n) (2-)(n> or =7), while smaller C(n)H(m) (2-) with n< or =6 could not be observed. BeC(n) (2-) (n=4,6,8,10), Be(2)C(6) (2-), as well as BeC(8)H(m) (2-) (with m=2 and/or m=1) were observed for toluene vapor flooding of a Cs(+)-bombarded beryllium metal foil. The metastable pentamer (9)Be(12)C(4) (2-) at mz=28.5 was the smallest and lightest dianion molecule that we could detect. The small dianion clusters of SC(n) (2-), OC(n) (2-), BeC(n) (2-), and SiO(m)C(n) (2-) (m=0,1,2) have different abundance patterns. A resemblance exists between the abundance patterns of BeC(n) (2-) and SiC(n) (2-), even though calculated molecular structures of BeC(6) (2-) and SiC(6) (2-) are different. The abundance pattern of SC(n) (2-) is fairly similar to that of C(n) (2-).
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Affiliation(s)
- Klaus Franzreb
- Department of Chemistry and Biochemistry, Arizona State University, Tempe, AZ 85287, USA
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Trindle C, Yumak A. Open Shell Dianions Likely To Be Stable in the Gas Phase with Respect to Autoionization. J Chem Theory Comput 2005; 1:1038-44. [PMID: 26641919 DOI: 10.1021/ct049845h] [Citation(s) in RCA: 4] [Impact Index Per Article: 0.2] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/28/2022]
Abstract
We address the challenge set by Dreuw and Cederbaum [Dreuw, A.; Cederbaum, L. S. Chem. Rev. 2002, 102, 181-200] to develop a set of "small" open shell stable dianions. We offer two families of such species, based on a central diradical center with attached anionic sites. Both families achieve dianion stabilization through alternating zones of positive and negative charge. First, quasi-linear systems such as NB(C2)n-Q-(C2)nBN become diradical dianions stable to autoionization in two cases: (a) for Q a divalent (carbene) carbon when n is two or greater and (b) for Q a C4 ring diradical when n is one or greater. Second, carbenes with certain anionic aromatic substituents can be stable with respect to autoionization. π-Acid substituted carbenes (A2Q) have triplet ground states generally. If A is cyclopentadienyl anion stabilized by cyano substitution, the resulting triplet dianion is stable with respect to autoionization. In bisphenyl carbenes the triplet is relatively stabilized when ortho substituents force the system toward D2d symmetry. The dianion of bis(orthochlorophenyl) carbene produced by para-substitution with BN retains the triplet preference and is stable with respect to autoionization. These results obtained first by density functional calculations in a small basis, B3LYP/6-31G(d), are confirmed and extended by ROMP2 and CCSD calculations in a more flexible basis, 6-31+G(d). DFT has a systematic bias against systems with excess electrons, which is paradoxically a virtue in the screening of candidate dianions since the DFT calculation does not make false predictions of stability.
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Affiliation(s)
- Carl Trindle
- Department of Chemistry, University of Virginia, Charlottesville Virginia 22904.,Department of Physics, Marmara University, Istanbul Turkey
| | - Ayse Yumak
- Department of Chemistry, University of Virginia, Charlottesville Virginia 22904.,Department of Physics, Marmara University, Istanbul Turkey
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Gnaser H, Dreuw A, Cederbaum LS. Discovery of a new class of stable gas-phase dianions: Mixed oxygen–carbon cluster OCn2− (n=5–19). J Chem Phys 2002. [DOI: 10.1063/1.1506908] [Citation(s) in RCA: 20] [Impact Index Per Article: 0.9] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/14/2022] Open
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Affiliation(s)
- Andreas Dreuw
- Theoretische Chemie, Physikalisch-Chemisches Institut, Universität Heidelberg, Im Neuenheimer Feld 229, 69120 Heidelberg, Germany.
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Sommerfeld T, Tarantelli F, Meyer HD, Cederbaum LS. Ab initiocalculation of energies and lifetimes of metastable dianions: The C22− resonance. J Chem Phys 2000. [DOI: 10.1063/1.481236] [Citation(s) in RCA: 35] [Impact Index Per Article: 1.5] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/14/2022] Open
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Wang LS, Wang XB. Probing Free Multiply Charged Anions Using Photodetachment Photoelectron Spectroscopy. J Phys Chem A 2000. [DOI: 10.1021/jp9940093] [Citation(s) in RCA: 175] [Impact Index Per Article: 7.3] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/29/2022]
Affiliation(s)
- Lai-Sheng Wang
- Department of Physics, Washington State University, 2710 University Drive, Richland, Washington 99352, and W. R. Wiley Environmental Molecular Sciences Laboratory, MS K8-88, P.O. Box 999, Pacific Northwest National Laboratory, Richland, Washington 99352
| | - Xue-Bin Wang
- Department of Physics, Washington State University, 2710 University Drive, Richland, Washington 99352, and W. R. Wiley Environmental Molecular Sciences Laboratory, MS K8-88, P.O. Box 999, Pacific Northwest National Laboratory, Richland, Washington 99352
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Ding CF, Wang XB, Wang LS. Photoelectron Spectroscopy of Doubly Charged Anions: Intramolecular Coulomb Repulsion and Solvent Stabilization. J Phys Chem A 1998. [DOI: 10.1021/jp982698x] [Citation(s) in RCA: 70] [Impact Index Per Article: 2.7] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/28/2022]
Affiliation(s)
- Chuan-Fan Ding
- Department of Physics, Washington State University, Richland, Washington 99352, and Environmental Molecular Sciences Laboratory, Pacific Northwest National Laboratory, MS K8-88, P.O. Box 999, Richland, Washington 99352
| | - Xue-Bin Wang
- Department of Physics, Washington State University, Richland, Washington 99352, and Environmental Molecular Sciences Laboratory, Pacific Northwest National Laboratory, MS K8-88, P.O. Box 999, Richland, Washington 99352
| | - Lai-Sheng Wang
- Department of Physics, Washington State University, Richland, Washington 99352, and Environmental Molecular Sciences Laboratory, Pacific Northwest National Laboratory, MS K8-88, P.O. Box 999, Richland, Washington 99352
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Affiliation(s)
- A Van Orden
- Department of Chemistry, University of California, Berkeley 94720, USA
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Dolgounitcheva O, Zakrzewski VG, Ortiz JV. Structure, bonding, and energetics of C72− isomers. J Chem Phys 1998. [DOI: 10.1063/1.476543] [Citation(s) in RCA: 13] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/14/2022] Open
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