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Borgeaud Dit Avocat DP, Yang H, Nitsche A, Wenger J, Yoder BL, Signorell R. Out-of-focus spatial map imaging of magnetically deflected sodium ammonia clusters. Phys Chem Chem Phys 2024; 26:16972-16979. [PMID: 38842057 PMCID: PMC11186454 DOI: 10.1039/d4cp00788c] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/23/2024] [Accepted: 05/23/2024] [Indexed: 06/07/2024]
Abstract
This paper introduces out-of-focus spatial map imaging (SMI) as a detection method for magnetic deflection of molecular/cluster beams, using Nam(NH3)n to illustrate its capabilities. This method enables imaging of the complete spatial distribution, simplifying measurements and allowing for cluster-size-resolved analysis by shifting away from traditional in-focus SMI conditions. Incorporating out-of-focus SMI with TOF-MS and velocity map imaging into a single setup allows for direct assessment of clusters' magnetic moments without needing to pre-select velocities. Key findings include a slower relaxation for Na(NH3)4 compared to Na(NH3)3 and Na(NH3)5, unexpectedly high deflection for larger clusters up to Na(NH3)9, hinting at changes in cluster dynamics as the first solvation shell closes. The study also covers the first measurements of Na2(NH3)1 and Na3(NH3)n, showing distinct deflection behaviors and underscoring the improved capabilities of the new detection method.
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Affiliation(s)
| | - H Yang
- Department of Chemistry and Applied Biosciences, ETH Zurich, CH-8093 Zurich, Switzerland.
| | - A Nitsche
- Department of Chemistry and Applied Biosciences, ETH Zurich, CH-8093 Zurich, Switzerland.
| | - J Wenger
- Department of Chemistry and Applied Biosciences, ETH Zurich, CH-8093 Zurich, Switzerland.
| | - B L Yoder
- Department of Chemistry and Applied Biosciences, ETH Zurich, CH-8093 Zurich, Switzerland.
| | - R Signorell
- Department of Chemistry and Applied Biosciences, ETH Zurich, CH-8093 Zurich, Switzerland.
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Barnes J, Borgeaud dit Avocat DP, Simmen E, Yang H, Yoder BL, Signorell R. Comparison of Magnetic Deflection among Neutral Sodium-Doped Clusters: Na(H 2O) n, Na(NH 3) n, Na(MeOH) n, and Na(DME) n. J Phys Chem A 2023; 127:8544-8555. [PMID: 37794760 PMCID: PMC10591511 DOI: 10.1021/acs.jpca.3c03820] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/06/2023] [Revised: 09/06/2023] [Indexed: 10/06/2023]
Abstract
Using a pulsed Stern-Gerlach deflection experiment, we present the results of a comparative study on the magnetic properties of neutral sodium-doped solvent clusters Na(Sol)n with n = 1-4 (Sol: H2O, NH3, CH3OH, CH3OCH3). Experimental deflection ratios are compared with values calculated from molecular dynamics simulations. NaNH3 and NaH2O are deflected as a spin 1/2 system, consistent with spin transitions occurring on a time scale significantly longer than 100 μs. For all other clusters, reduced deflection is observed. The observed magnetic deflection behavior is correlated to the number of thermally populated rotational states in the clusters. We discuss that spin-rotational couplings allow for avoided crossings and a reduction in the effective magnetic moment of the cluster. This work attempts to understand the evolution of magnetic properties in isolated weakly bound clusters and is relevant to diamagnetic and paramagnetic species expected to exist in solvated electron systems.
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Affiliation(s)
- Jonathan
V. Barnes
- Department of Chemistry and
Applied Biosciences, ETH Zürich, Vladimir-Prelog-Weg 2, Zürich 8093, Switzerland
| | | | - Edith Simmen
- Department of Chemistry and
Applied Biosciences, ETH Zürich, Vladimir-Prelog-Weg 2, Zürich 8093, Switzerland
| | - Huanyu Yang
- Department of Chemistry and
Applied Biosciences, ETH Zürich, Vladimir-Prelog-Weg 2, Zürich 8093, Switzerland
| | - Bruce L. Yoder
- Department of Chemistry and
Applied Biosciences, ETH Zürich, Vladimir-Prelog-Weg 2, Zürich 8093, Switzerland
| | - Ruth Signorell
- Department of Chemistry and
Applied Biosciences, ETH Zürich, Vladimir-Prelog-Weg 2, Zürich 8093, Switzerland
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3
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Kurahashi M. Use of hexapole magnet and spin flipper combined with time-of-flight analysis to characterize state-selected paramagnetic atomic/molecular beams. THE REVIEW OF SCIENTIFIC INSTRUMENTS 2021; 92:013201. [PMID: 33514247 DOI: 10.1063/5.0031903] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Abstract] [Track Full Text] [Subscribe] [Scholar Register] [Received: 10/05/2020] [Accepted: 12/12/2020] [Indexed: 06/12/2023]
Abstract
In the past, the Stern-Gerlach experiment has been used as a standard method for analyzing the population of magnetic substates contained in spin-polarized and/or state-selected atomic/molecular beams. However, this experiment is quite demanding due to its low signal intensity and difficulty in beam alignment. The present study shows that the use of a hexapole magnet and a spin flipper, together with the time-of-flight analysis, allows us to conduct an almost equivalent analysis while greatly improving the signal intensity. Applications to the analysis of spin-polarized triplet excited helium and state-selected O2( 3 Σg -) beams are presented.
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Affiliation(s)
- Mitsunori Kurahashi
- National Institute for Materials Science, 1-2-1 Sengen, Tsukuba, Ibaraki 305-0047, Japan
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4
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Barnes JV, Beck M, Hartweg S, Luski A, Yoder BL, Narevicius J, Narevicius E, Signorell R. Magnetic deflection of neutral sodium-doped ammonia clusters. Phys Chem Chem Phys 2021; 23:846-858. [DOI: 10.1039/d0cp04647g] [Citation(s) in RCA: 5] [Impact Index Per Article: 1.7] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/21/2022]
Abstract
A new Stern–Gerlach setup elucidates the spin relaxation dynamics of small weakly-bound Na(NH3)n clusters.
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Affiliation(s)
- J. V. Barnes
- Department of Chemistry and Applied Biosciences, ETH Zürich
- Zürich
- Switzerland
| | - M. Beck
- Department of Chemistry and Applied Biosciences, ETH Zürich
- Zürich
- Switzerland
| | - S. Hartweg
- Department of Chemistry and Applied Biosciences, ETH Zürich
- Zürich
- Switzerland
| | - A. Luski
- Department of Chemical Physics, Weizmann Institute of Science
- Rehovot
- Israel
| | - B. L. Yoder
- Department of Chemistry and Applied Biosciences, ETH Zürich
- Zürich
- Switzerland
| | - J. Narevicius
- Department of Chemical Physics, Weizmann Institute of Science
- Rehovot
- Israel
| | - E. Narevicius
- Department of Chemical Physics, Weizmann Institute of Science
- Rehovot
- Israel
| | - R. Signorell
- Department of Chemistry and Applied Biosciences, ETH Zürich
- Zürich
- Switzerland
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Sticking Probability and Reactivity of Hyperthermal O2 Molecules Impinging on CO Pre-covered Pd(100): Effect of Rotational States with K > 1. Top Catal 2015. [DOI: 10.1007/s11244-015-0408-7] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 10/23/2022]
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6
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Kurahashi M, Yamauchi Y. Spin correlation in O(2) chemisorption on Ni(111). PHYSICAL REVIEW LETTERS 2015; 114:016101. [PMID: 25615482 DOI: 10.1103/physrevlett.114.016101] [Citation(s) in RCA: 10] [Impact Index Per Article: 1.1] [Reference Citation Analysis] [Abstract] [Track Full Text] [Subscribe] [Scholar Register] [Received: 10/22/2014] [Indexed: 06/04/2023]
Abstract
Molecular oxygen (O(2)) is a paramagnetic linear molecule, yet how its electron spin affects the chemisorption probability remains unclear. We here present the first spin- and alignment-resolved O(2) chemisorption experiment conducted with a single spin-rotational state-selected O(2) beam and a magnetized Ni(111) surface. The results show that the O(2) sticking probability is higher when its spin is oriented antiparallel to the majority spin direction of the Ni substrate. The spin dependence becomes more significant at low translational energy, and amounts to over 40% at thermal energy. This strong spin effect suggests that incident O(2) molecules keep high spin polarizations even at the position of the dissociation barrier.
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Affiliation(s)
- Mitsunori Kurahashi
- National Institute for Materials Science, 1-2-1 Sengen, Tsukuba, Ibaraki 305-0047, Japan
| | - Yasushi Yamauchi
- National Institute for Materials Science, 1-2-1 Sengen, Tsukuba, Ibaraki 305-0047, Japan
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Alagia M, Aquilanti V, Ascenzi D, Balucani N, Cappelletti D, Cartechini L, Casavecchia P, Pirani F, Sanchini G, Volpi GG. Magnetic Analysis of Supersonic Beams of Atomic Oxygen, Nitrogen, and Chlorine Generated from a Radio-Frequency Discharge. Isr J Chem 2013. [DOI: 10.1002/ijch.199700038] [Citation(s) in RCA: 87] [Impact Index Per Article: 7.9] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/06/2022]
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Rohrmann U, Schäfer R. Stern-Gerlach experiments on Mn@Sn12: identification of a paramagnetic superatom and vibrationally induced spin orientation. PHYSICAL REVIEW LETTERS 2013; 111:133401. [PMID: 24116778 DOI: 10.1103/physrevlett.111.133401] [Citation(s) in RCA: 32] [Impact Index Per Article: 2.9] [Reference Citation Analysis] [Abstract] [Track Full Text] [Subscribe] [Scholar Register] [Received: 05/17/2013] [Indexed: 06/02/2023]
Abstract
Beam deflection experiments in inhomogeneous magnetic fields reveal a new limiting case of the magnetization distribution of isolated clusters. Endohedrally doped clusters are produced in a temperature controlled, cryogenically cooled laser ablation source. Temperature dependent experiments indicate a crucial contribution of molecular vibrations to the spin dynamics of Mn@Sn12. In its vibrational ground state the cluster behaves magnetically like a paramagnetic atom, with quantized spin states. However, excited molecular vibrations induce spin orientation in the magnetic field.
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Affiliation(s)
- Urban Rohrmann
- Eduard-Zintl-Institut für Anorganische und Physikalische Chemie, Technische Universität Darmstadt, Petersenstraße 20, 64287 Darmstadt, Germany
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Aquilanti V, Ascenzi D, Cappelletti D, Pirani F. Magnetic Analysis of Atomic and Molecular Beams. Recent Applications. J CHIN CHEM SOC-TAIP 2013. [DOI: 10.1002/jccs.199500037] [Citation(s) in RCA: 5] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/06/2022]
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10
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Gershnabel E, Shapiro M, Averbukh IS. Stern-Gerlach deflection of field-free aligned paramagnetic molecules. J Chem Phys 2011; 135:194310. [DOI: 10.1063/1.3662135] [Citation(s) in RCA: 12] [Impact Index Per Article: 0.9] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/11/2022] Open
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11
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Kurahashi M, Yamauchi Y. Production of a single spin-rotational state [(J,M) = (2,2)] selected molecular oxygen (3Sigma(g)-) beam by a hexapole magnet. THE REVIEW OF SCIENTIFIC INSTRUMENTS 2009; 80:083103. [PMID: 19725642 DOI: 10.1063/1.3206299] [Citation(s) in RCA: 11] [Impact Index Per Article: 0.7] [Reference Citation Analysis] [Abstract] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 05/28/2023]
Abstract
A state-selected O(2)((3)Sigma(g)(-)) molecular beam, in which nearly 100% of the molecules are in the spin-rotational state of (J,M) = (2,2), has been produced by combining a supersonic seeded O(2) beam with a hexapole magnet. The (2,-2) beam has also been obtained by the state inversion of the (2,2) beam through the nonadiabatic passage in a reversing longitudinal magnetic field along the beam axis. The intensities of the other (2,M) states, which appear when applying additional transverse magnetic fields to the reversing field region, were well reproduced by the Majorana's formula for J = 2. The (2,+/-2) beam, for which we can determine the spin and rotational angular momenta of O(2) almost independently, is the most promising probe for studying the spin effects as well as the steric effects in O(2) molecular scattering.
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Affiliation(s)
- Mitsunori Kurahashi
- National Institute for Materials Science, 1-2-1 Sengen, Tsukuba, Ibaraki 305-0047, Japan
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12
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Miyajima K, Knickelbein MB, Nakajima A. Stern-gerlach study of multidecker lanthanide-cyclooctatetraene sandwich clusters. J Phys Chem A 2008; 112:366-75. [PMID: 18166028 DOI: 10.1021/jp0766196] [Citation(s) in RCA: 59] [Impact Index Per Article: 3.7] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/30/2022]
Abstract
Multilayer lanthanide-cyclooctatetraene organometallic clusters, Lnn(C8H8)m (Ln = Eu, Tb, Ho, Tm; n = 1-7; m = n - 1, n, n + 1) were produced by a laser vaporization synthesis method. The magnetic deflections of these organometallic sandwich clusters were measured by a molecular beam magnetic deflection technique. Most of the sandwich species displayed one-sided deflection, while some of smaller Ln-C8H8 clusters showed symmetric broadening without or with only very small (or absent) net high-field deflection. In general, the total magnetic moments, calculated from the magnitude of the beams deflections, increase with the number of lanthanide atoms (i.e., with increasing sandwich layers); however for Tb-, Ho-, and Tm-C8H8 clusters with n > 3, the suppression of the magnetic moments was observed, possibly through antiferromagnetic interactions. For Eu-C8H8 clusters, we observe a linear increase of the magnetic moments with the number of Eu atoms up to n = 7, with average magnetic moment per Eu atom around 7 muB--similar to that displayed by conventionally synthesized mononuclear EuIIC8H8 complexes, indicating that Eu atoms exist as Eu2+ ions in the full sandwich Eun(C8H8)n+1 clusters. These results suggest that Eun(C8H8)n+1 is a promising candidate for a high-spin, one-dimensional building block in organometallic magnetic materials.
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Affiliation(s)
- Ken Miyajima
- Department of Chemistry, Faculty of Science and Technology, Keio University, 3-14-1 Hiyoshi, Kohoku-ku, Yokohama 223-8522, Japan
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Xu X, Yin S, Moro R, de Heer WA. Magnetic moments and adiabatic magnetization of free cobalt clusters. PHYSICAL REVIEW LETTERS 2005; 95:237209. [PMID: 16384341 DOI: 10.1103/physrevlett.95.237209] [Citation(s) in RCA: 81] [Impact Index Per Article: 4.3] [Reference Citation Analysis] [Abstract] [Track Full Text] [Subscribe] [Scholar Register] [Received: 02/18/2005] [Revised: 06/13/2005] [Indexed: 05/05/2023]
Abstract
Magnetizations and magnetic moments of free cobalt clusters Co(N) (12 < N < 200) in a cryogenic (25 K < or = T < or = 100 K) molecular beam were determined from Stern-Gerlach deflections. All clusters preferentially deflect in the direction of the increasing field and the average magnetization resembles the Langevin function for all cluster sizes even at low temperatures. We demonstrate in the avoided crossing model that the average magnetization may result from adiabatic processes of rotating and vibrating clusters in the magnetic field and that spin relaxation is not involved. This resolves a long-standing problem in the interpretation of cluster beam deflection experiments with implications for nanomagnetic systems in general.
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Affiliation(s)
- Xiaoshan Xu
- School of Physics, Georgia Institute of Technology, Atlanta, Georgia 30332, USA
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14
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Knickelbein MB. Spin relaxation in isolated molecules and clusters: The interpretation of Stern-Gerlach experiments. J Chem Phys 2004; 121:5281-3. [PMID: 15352821 DOI: 10.1063/1.1781156] [Citation(s) in RCA: 27] [Impact Index Per Article: 1.4] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/15/2022] Open
Abstract
Intramolecular spin relaxation may occur in isolated molecules or clusters provided that the density of rovibrational eigenstates is sufficiently high to serve as an energy bath and angular momentum is conserved. In the coupled, zero-field limit, total angular momentum (J) is the sum of spin (S) and rotational (N) momenta such that J and M(J) are good angular momentum quantum numbers. In the coupled limit, transitions between Zeeman levels (Delta M(J)++0) cannot occur in the absence of an external torque. However, in the high-field limit, J and M(J) are no longer good quantum numbers, as N and S are decoupled and only their projections on the z axis defined by the external field are invariant. In this case M(N) and M(S) remain as good quantum numbers so that angular momentum conserving transitions can occur subject to the selection rule Delta M(N)=-Delta M(S). Determination of the magnetic moments of isolated molecules and clusters via a thermodynamics-based analysis requires that their magnetizations are measured at sufficiently large fields that spin-rotation effects become negligible and the Zeeman level structure approaches the free-spin case.
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Affiliation(s)
- Mark B Knickelbein
- Chemistry Division, Argonne National Laboratory, Argonne, Illinois 60439, USA
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15
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Aquilanti V, Ascenzi D, Cappelletti D, Pirani F. Reply to the Comment on “Rotational Alignment in Supersonic Seeded Beams of Molecular Oxygen” (by Charles D. Pibel, Joshua B. Halpern). J Phys Chem A 1999. [DOI: 10.1021/jp9838846] [Citation(s) in RCA: 6] [Impact Index Per Article: 0.2] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/28/2022]
Affiliation(s)
| | - Daniela Ascenzi
- Dipartimento di Chimica dell'Università, I-06123 Perugia, Italy
| | | | - Fernando Pirani
- Dipartimento di Chimica dell'Università, I-06123 Perugia, Italy
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16
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Brault P, Range H, Toennies JP. Molecular beam studies of sticking of oxygen on the Rh(111) surface. J Chem Phys 1997. [DOI: 10.1063/1.473951] [Citation(s) in RCA: 15] [Impact Index Per Article: 0.6] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/14/2022] Open
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17
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Aquilanti V, Ascenzi D, Cappelletti D, Pirani F. Velocity dependence of collisional alignment of oxygen molecules in gaseous expansions. Nature 1994. [DOI: 10.1038/371399a0] [Citation(s) in RCA: 136] [Impact Index Per Article: 4.5] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/09/2022]
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Aquilanti V, Candori R, Cappelletti D, Lorent V, Pirani F. A magnetically selected beam of chlorine atoms. Chem Phys Lett 1992. [DOI: 10.1016/0009-2614(92)85444-f] [Citation(s) in RCA: 14] [Impact Index Per Article: 0.4] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/28/2022]
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