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Müller D, Dopfer O. Microsolvation of H 2O +, H 3O +, and CH 3OH 2+ by He in a cryogenic ion trap: structure of solvation shells. Phys Chem Chem Phys 2022; 24:11222-11233. [PMID: 35481676 DOI: 10.1039/d2cp01192a] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/21/2022]
Abstract
Due to the weak interactions of He atoms with neutral molecules and ions, the preparation of size-selected clusters for the spectroscopic characterization of their structures, energies, and large amplitude motions is a challenging task. Herein, we generate H2O+Hen (n ≤ 9) and H3O+Hen (n ≤ 5) clusters by stepwise addition of He atoms to mass-selected ions stored in a cryogenic 22-pole ion trap held at 5 K. The population of the clusters as a function of n provides insight into the structure of the first He solvation shell around these ions given by the anisotropy of the cation-He interaction potential. To rationalize the observed cluster size distributions, the structural, energetic, and vibrational properties of the clusters are characterized by ab initio calculations up to the CCSD(T)/aug-cc-pVTZ level. The cluster growth around both the open-shell H2O+ and closed-shell H3O+ ions begins by forming nearly linear and equivalent OH⋯He hydrogen bonds (H-bonds) leading to symmetric structures. The strength of these H-bonds decreases slightly with n due to noncooperative three-body induction forces and is weaker for H3O+ than for H2O+ due to both enhanced charge delocalization and reduced acidity of the OH protons. After filling all available H-bonded sites, addition of further He ligands around H2O+ (n = 3-4) occurs at the electrophilic singly occupied 2pz orbital of O leading to O⋯He p-bonds stabilized by induction and small charge transfer from H2O+ to He. As this orbital is filled for H3O+, He atoms occupy in the n = 4-6 clusters positions between the H-bonded He atoms, leading to a slightly distorted regular hexagon ring for n = 6. Comparison between H3O+Hen and CH3OH2+Hen illustrates that CH3 substitution substantially reduces the acidity of the OH protons, so that only clusters up to n = 2 can be observed. The structure of the solvation sub-shells is visible in both the binding energies and the predicted vibrational OH stretch and bend frequencies.
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Affiliation(s)
- David Müller
- Institut für Optik und Atomare Physik, Technische Universität Berlin, Hardenbergstr. 36, 10623 Berlin, Germany.
| | - Otto Dopfer
- Institut für Optik und Atomare Physik, Technische Universität Berlin, Hardenbergstr. 36, 10623 Berlin, Germany.
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2
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Valdés Á, Prosmiti R. Quantum effects on the stability of the He 5 I 2 van der Waals conformers. J Comput Chem 2019; 40:2200-2206. [PMID: 31148224 DOI: 10.1002/jcc.25870] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/11/2019] [Revised: 04/10/2019] [Accepted: 05/16/2019] [Indexed: 11/05/2022]
Abstract
We present 15-dimensional quantum multiconfiguration time-dependent Hartree calculations of the vibrational levels of the He5 I2 van der Waals (vdW) complex employing an ab initio-based potential energy surface (PES). The energies and spatial features of such bound structures are analyzed, providing predictions on the structures and relative stabilities of its three lowest isomers. We found that the most stable isomer corresponds to all five He atoms encircling the I2 molecule, indicating that in this case the anharmonic quantum effects do not stabilize the isomers involving a He atom in a linear configuration as reported previously for the smaller HeN I2 systems. Such finding provides information on the overall structuring of the finite-size-solvent systems, highlighting the intriguing interplay between weak intermolecular interactions and quantum effects. © 2019 Wiley Periodicals, Inc.
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Affiliation(s)
- Álvaro Valdés
- Departamento de Física, Universidad Nacional de Colombia, Calle 26, Cra 39, Edificio 404, Bogotá, Colombia
| | - Rita Prosmiti
- Departamento PAMS, Instituto de Física Fundamental (IFF-CSIC), CSIC, Serrano 123, 28006, Madrid, Spain
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3
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Solimannejad M, Mirhoseini BS, Esrafili MD. Microsolvation of CH+ in helium: An ab initio study. JOURNAL OF THEORETICAL & COMPUTATIONAL CHEMISTRY 2016. [DOI: 10.1142/s0219633616500188] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.1] [Reference Citation Analysis] [Abstract] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 11/18/2022]
Abstract
In the present study, microsolvation and interaction of the CH[Formula: see text] cation with He[Formula: see text] clusters are investigated by means of ab initio calculations at MP2/aug-cc-pVTZ and QCISD/aug-cc-pVTZ levels. Stabilization energies of the studied complexes including basis set superposition error (BSSE) and zero point energy (ZPE) corrections are in the range of [Formula: see text][Formula: see text]kJ/mol and [Formula: see text][Formula: see text]kJ/mol. A good linear correlation is found between the stabilization energy and stretching frequency shift ([Formula: see text]) in the studied complexes. According to energy decomposition analysis, it is found that polarization effects are the major source of the attraction in these complexes.
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Affiliation(s)
- Mohammad Solimannejad
- Department of Chemistry, Faculty of Science, Arak University, Arak 38156-8-8349, Iran
| | | | - Mehdi D. Esrafili
- Laboratory of Theoretical Chemistry, Department of Chemistry, University of Maragheh, Maragheh 55138-64596, Iran
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4
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González Flórez AI, Ahn DS, Gewinner S, Schöllkopf W, von Helden G. IR spectroscopy of protonated leu-enkephalin and its 18-crown-6 complex embedded in helium droplets. Phys Chem Chem Phys 2015; 17:21902-11. [DOI: 10.1039/c5cp02172c] [Citation(s) in RCA: 45] [Impact Index Per Article: 5.0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/17/2022]
Abstract
Ultracold IR spectra of protonated leu-enkephalin and its 18-crown-6 complex embedded in superfluid helium droplets have been recorded using a free-electron laser as radiation source.
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Affiliation(s)
| | - Doo-Sik Ahn
- Fritz-Haber-Institut der Max-Planck-Gesellschaft
- 14195 Berlin
- Germany
| | - Sandy Gewinner
- Fritz-Haber-Institut der Max-Planck-Gesellschaft
- 14195 Berlin
- Germany
| | | | - Gert von Helden
- Fritz-Haber-Institut der Max-Planck-Gesellschaft
- 14195 Berlin
- Germany
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5
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Pérez de Tudela R, Barragán P, Valdés Á, Prosmiti R. Energetics and solvation structure of a dihalogen dopant (I2) in (4)He clusters. J Phys Chem A 2014; 118:6492-500. [PMID: 24869502 DOI: 10.1021/jp502994g] [Citation(s) in RCA: 13] [Impact Index Per Article: 1.3] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/30/2022]
Abstract
The energetics and structure of small HeNI2 clusters are analyzed as the size of the system changes, with N up to 38. The full interaction between the I2 molecule and the He atoms is based on analytical ab initio He-I2 potentials plus the He-He interaction, obtained from first-principle calculations. The most stable structures, as a function of the number of solvent He atoms, are obtained by employing an evolutionary algorithm and compared with CCSD(T) and MP2 ab initio computations. Further, the classical description is completed by explicitly including thermal corrections and quantum features, such as zero-point-energy values and spatial delocalization. From quantum PIMC calculations, the binding energies and radial/angular probability density distributions of the thermal equilibrium state for selected-size clusters are computed at a low temperature. The sequential formation of regular shell structures is analyzed and discussed for both classical and quantum treatments.
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López-Durán D, Rodríguez-Cantano R, González-Lezana T, Delgado-Barrio G, Villarreal P, Yurtsever E, Gianturco FA. Weakly bound finite systems: (⁴He)N-Rb₂(³Σu), clustering structures from a quantum Monte Carlo approach. JOURNAL OF PHYSICS. CONDENSED MATTER : AN INSTITUTE OF PHYSICS JOURNAL 2012; 24:104014. [PMID: 22353432 DOI: 10.1088/0953-8984/24/10/104014] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.2] [Reference Citation Analysis] [Abstract] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 05/31/2023]
Abstract
We report here ((4)He)(N)-Rb(2)((3)Σ(u)) complexes, 2 ≤ N ≤ 20, analysed through a quantum diffusion Monte Carlo stochastic approach. The calculations show that the spin stretched dimer molecule is bound outside the pure He sub-complex, due to the stronger He-He potential as compared with the He-Rb(2) interaction, while the rare gas atom moiety presents, in turn, a shell-like structure with ten He adatoms completing the first shell. Our results agree with previous findings on this and similarly weakly interacting systems.
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Affiliation(s)
- D López-Durán
- Instituto de Física Fundamental, CSIC, Serrano 123, 28006 Madrid, Spain
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Marinetti F, Gianturco FA. Water as a solute: competitive shell formation in (He,Ne) mixed microdroplets. Phys Chem Chem Phys 2011; 13:2136-44. [PMID: 21116567 DOI: 10.1039/c0cp01342k] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.1] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/21/2022]
Abstract
Quantum Monte Carlo (QMC) stochastic calculations are carried out for a series of mixed rare gas clusters containing He and Ne which further include one H(2)O molecule as a single dopant. The ab initio potentials employed in the calculations, and the structural details provided by the QMC results, clearly reveal that the differences in the interaction forces which exist between the two solvent adatoms and the molecular solute are causing strongly competing environments that generate preferential shell structuring when surrounding the water molecule. The different behaviour of the two solvents, and the energetics of mixing, are analyzed in detail for small aggregates and for larger mixtures, revealing structural effects which originate from the different networking between solvent adatoms.
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Affiliation(s)
- F Marinetti
- Department of Chemistry and CNISM, University of Rome La Sapienza, Piazzale A. Moro 5, 00185 Rome, Italy
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Raston PL, Knapp CJ, Jäger W. Rotovibrational spectroscopy of hydrogen peroxide embedded in superfluid helium nanodroplets. Phys Chem Chem Phys 2011; 13:18789-98. [DOI: 10.1039/c1cp21348b] [Citation(s) in RCA: 18] [Impact Index Per Article: 1.4] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/21/2022]
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Smolarek S, Brauer NB, Buma WJ, Drabbels M. IR Spectroscopy of Molecular Ions by Nonthermal Ion Ejection from Helium Nanodroplets. J Am Chem Soc 2010; 132:14086-91. [DOI: 10.1021/ja1034655] [Citation(s) in RCA: 51] [Impact Index Per Article: 3.6] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/29/2022]
Affiliation(s)
- Szymon Smolarek
- University of Amsterdam, P.O. Box 94157, 1090 GD Amsterdam, The Netherlands, and Laboratoire de Chimie Physique Moléculaire, Ecole Polytechnique Fédérale de Lausanne (EPFL), CH-1015 Lausanne, Switzerland
| | - Nils B. Brauer
- University of Amsterdam, P.O. Box 94157, 1090 GD Amsterdam, The Netherlands, and Laboratoire de Chimie Physique Moléculaire, Ecole Polytechnique Fédérale de Lausanne (EPFL), CH-1015 Lausanne, Switzerland
| | - Wybren J. Buma
- University of Amsterdam, P.O. Box 94157, 1090 GD Amsterdam, The Netherlands, and Laboratoire de Chimie Physique Moléculaire, Ecole Polytechnique Fédérale de Lausanne (EPFL), CH-1015 Lausanne, Switzerland
| | - Marcel Drabbels
- University of Amsterdam, P.O. Box 94157, 1090 GD Amsterdam, The Netherlands, and Laboratoire de Chimie Physique Moléculaire, Ecole Polytechnique Fédérale de Lausanne (EPFL), CH-1015 Lausanne, Switzerland
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Marinetti F, Yurtsever E, Gianturco FA. HCHO in a Cold, Quantum Solvent: Size and Shape of Its “Bubbles” in 4He Droplets from Stochastic Simulations. J Phys Chem A 2010; 114:9725-32. [DOI: 10.1021/jp1018857] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.1] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/28/2022]
Affiliation(s)
- F. Marinetti
- Department of Chemistry and CNISM, University of Rome La Sapienza, Piazzale A. Moro 5, 00185 Rome, Italy, and Department of Chemistry, Koç, University, Rumelifeneriyolu, 34450 Sariyer, Istanbul, Turkey
| | - E. Yurtsever
- Department of Chemistry and CNISM, University of Rome La Sapienza, Piazzale A. Moro 5, 00185 Rome, Italy, and Department of Chemistry, Koç, University, Rumelifeneriyolu, 34450 Sariyer, Istanbul, Turkey
| | - F. A. Gianturco
- Department of Chemistry and CNISM, University of Rome La Sapienza, Piazzale A. Moro 5, 00185 Rome, Italy, and Department of Chemistry, Koç, University, Rumelifeneriyolu, 34450 Sariyer, Istanbul, Turkey
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Slavícek P, Lewerenz M. Snowballs, quantum solvation and coordination: lead ions inside small helium droplets. Phys Chem Chem Phys 2009; 12:1152-61. [PMID: 20094680 DOI: 10.1039/b918186e] [Citation(s) in RCA: 29] [Impact Index Per Article: 1.9] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/21/2022]
Abstract
Ab initio calculations are used to construct an analytical many-body potential for Pb(2+)He(n) and Pb(+)He(n) clusters which accounts for non pairwise additive interactions. The potential surface reproduces the global minima for cluster sizes ranging from n = 1 to n = 16 obtained from explicit ab initio calculations and found in a previous search for ultrahigh coordination numbers. Ground state energies and structures obtained by accurate diffusion quantum Monte Carlo calculations are used to investigate if quantum effects qualitatively affect the formation of coordination shells. For Pb(2+) doped clusters a first solvation shell is closed at n = 12 and gradually softened by additional helium atoms which start to form a distinct second shell only at n = 16. Spin-orbit coupling profoundly influences the structure of Pb(+)He(n) clusters and causes a gradual structural evolution without pronounced solvation shells.
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Affiliation(s)
- Petr Slavícek
- Department of Physical Chemistry, Institute of Chemical Technology Prague, Technická 6, 166 28 Prague 6, Czech Republic
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12
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Müller S, Mudrich M, Stienkemeier F. Alkali-helium snowball complexes formed on helium nanodroplets. J Chem Phys 2009; 131:044319. [PMID: 19655879 DOI: 10.1063/1.3180819] [Citation(s) in RCA: 40] [Impact Index Per Article: 2.7] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/14/2022] Open
Abstract
We systematically investigate the formation and stability of snowballs formed by femtosecond photoionization of small alkali clusters bound to helium nanodroplets. For all studied alkali species Ak = (Na,K,Rb,Cs) we observe the formation of snowballs Ak(+)He(N) when multiply doping the droplets. Fragmentation of clusters Ak(N) upon ionization appears to enhance snowball formation. In the case of Na and Cs we also detect snowballs Ak(2) (+)He(N) formed around Ak dimer ions. While the snowball progression for Na and K is limited to less than 11 helium atoms, the heavier atoms Rb and Cs feature wide distributions at least up to Ak(+)He(41). Characteristic steps in the mass spectra of Cs-doped helium droplets are found at positions consistent with predictions on the closure of the first shell of helium atoms around the Ak(+) ion based on variational Monte Carlo simulations.
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Affiliation(s)
- S Müller
- Physikalisches Institut, Universität Freiburg, 79104 Freiburg, Germany
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13
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Bovino S, Coccia E, Bodo E, Lopez-Durán D, Gianturco FA. Spin-driven structural effects in alkali doped (4)He clusters from quantum calculations. J Chem Phys 2009; 130:224903. [PMID: 19530785 DOI: 10.1063/1.3147466] [Citation(s) in RCA: 24] [Impact Index Per Article: 1.6] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/14/2022] Open
Abstract
In this paper, we carry out variational Monte Carlo and diffusion Monte Carlo (DMC) calculations for Li(2)((1)Sigma(g) (+))((4)He)(N) and Li(2)((3)Sigma(u) (+))((4)He)(N) with N up to 30 and discuss in detail the results of our computations. After a comparison between our DMC energies with the "exact" discrete variable representation values for the species with one (4)He, in order to test the quality of our computations at 0 K, we analyze the structural features of the whole range of doped clusters. We find that both species reside on the droplet surface, but that their orientation is spin driven, i.e., the singlet molecule is perpendicular and the triplet one is parallel to the droplet's surface. We have also computed quantum vibrational relaxation rates for both dimers in collision with a single (4)He and we find them to differ by orders of magnitude at the estimated surface temperature. Our results therefore confirm the findings from a great number of experimental data present in the current literature and provide one of the first attempts at giving an accurate, fully quantum picture for the nanoscopic properties of alkali dimers in (4)He clusters.
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Affiliation(s)
- S Bovino
- Department of Chemistry and CNISM, The University of Rome Sapienza, P.le A. Moro 5, 00185 Rome, Italy
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14
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Marinetti F, Bodo E, Gianturco FA, Yurtsever E. Energetics and structures of charged helium clusters: comparing stabilities of dimer and trimer cationic cores. Chemphyschem 2009; 9:2618-24. [PMID: 19012312 DOI: 10.1002/cphc.200800457] [Citation(s) in RCA: 10] [Impact Index Per Article: 0.7] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/07/2022]
Abstract
We present accurate ab initio calculations of the most stable structures of He(n)(+) clusters in order to determine the more likely ionic core arrangements existing after reaching structural equilibrium of the clusters. Two potential energy surfaces are presented: one for the He(2)(+) and the other with the He(3)(+) linear ion, both interacting with one He atom. The two computed potentials are in turn employed within a classical structure optimization where the overall interaction forces are obtained within the sum-of-potentials approximation described in the main text. Because of the presence of many-body effects within the ionic core, we find that the arrangements with He(3)(+) as a core turn out to be energetically preferred, leading to the formation of He(3)(+)(He)(n-3) stable aggregates. Nanoscopic considerations about the relative stability of clusters with the two different cores are shown to give us new information on the dynamical processes observed in the impact ionization experiments of pure helium clusters and the importance of pre-equilibrium evaporation of the ionic dimers in the ionized clusters.
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Affiliation(s)
- Fabio Marinetti
- Department of Chemistry, University of Rome La Sapienza and CNISM, Piazzale A. Moro 5, 00185 Rome, Italy
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15
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Coccia E, Marinetti F, Bodo E, Gianturco FA. Anionic microsolvation in helium droplets: OH−(He)N structures from classical and quantum calculations. J Chem Phys 2008; 128:134511. [DOI: 10.1063/1.2842082] [Citation(s) in RCA: 19] [Impact Index Per Article: 1.2] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/15/2022] Open
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16
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Marinetti F, Uranga-Piña L, Coccia E, López-Durán D, Bodo E, Gianturco FA. Microsolvation of Cationic Dimers in 4He Droplets: Geometries of (He)N (A = Li, Na, K) from Optimized Energies. J Phys Chem A 2007; 111:12289-94. [PMID: 17727278 DOI: 10.1021/jp0748361] [Citation(s) in RCA: 19] [Impact Index Per Article: 1.1] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/28/2022]
Abstract
Ab initio computed interaction forces are employed to describe the microsolvation of the A+2(2Sigma) (A=Li, Na, K) molecular ion in 4He clusters of small variable size. The minimum energy structures are obtained by performing energy minimization based on a genetic algorithm approach. The symmetry features of the collocation of solvent adatoms around the dimeric cation are analyzed in detail, showing that the selective growth of small clusters around the two sides of the ion during the solvation process is a feature common to all three dopants.
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Affiliation(s)
- F Marinetti
- Department of Chemistry, The University of Rome La Sapienza, Rome, Italy
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