Library

X
You have 0 saved results.
Mark results and click the "Add To Watchlist" link in order to add them to this list.
feed icon rss

Your email was sent successfully. Check your inbox.

An error occurred while sending the email. Please try again.

Proceed reservation?

Export
  • 1
    Electronic Resource
    Electronic Resource
    Anionic and Neutral States of Li3O (1994)
    s.l. : American Chemical Society
    The @journal of physical chemistry 〈Washington, DC〉 98 (1994), S. 8326-8330 
    Details
    Source: ACS Legacy Archives
    Topics: Chemistry and Pharmacology , Physics
    Type of Medium: Electronic Resource
    URL: http://dx.doi.org/10.1021/j100085a011
    Library Location Call Number Volume/Issue/Year Availability
    BibTip Others were also interested in ...
    Paper (German National Licenses)
    Fulltext
  • 2
    Electronic Resource
    Electronic Resource
    Inversion in the relative stabilities of HBO and BOH upon ionization (1999)
    College Park, Md. : American Institute of Physics (AIP)
    The Journal of Chemical Physics 110 (1999), S. 3765-3768 
    Details
    ISSN: 1089-7690
    Source: AIP Digital Archive
    Topics: Physics , Chemistry and Pharmacology
    Notes: Ab initio calculations of the HBO+→BOH+potential energy surface were performed at the QCISD(T)/6−311++G(2df,2pd) level of theory. A linear 2Σ+ +B=O-H species was found to be the global minimum for the cation although the linear 1Σ+ H-B(Triple Bond)O isomer is the global minimum on the neutral HBO→BOH surface. Which isomer of the cation appears in various experimental circumstances depends on how the cation is produced. Ionization of 1Σ+ HBO should occur near 13.2 eV and will produce the metastable linear H-B(Double Bond)O+(2Π) π-radical cation, which is 36.9 kcal/mol higher in energy than 2Σ+ +B(Double Bond)O-H and is separated from +B(Double Bond)O-H by a 36.3 kcal/mol classical barrier. Ionization of HBO with less than 37 kcal/mol of excess energy will thus yield 2Π H-B(Double Bond)O+; if the excess energy exceeds 37 kcal/mol, rearrangement to the 2Σ++B(Double Bond)O-H σ-radical cation can occur. Production of the cation via exothermic chemical reaction will likely give the more stable 2Σ+ +B(Double Bond)O-H isomer. The stability of the 2Σ+ +B(Double Bond)O-H cation relative to 2Π H-B(Double Bond)O+ is due primarily to the large difference in the energies required to remove an electron from a π bonding orbital in H-B(Triple Bond)O or from a nonbonding boron-localized σ orbital in BOH. © 1999 American Institute of Physics.
    Type of Medium: Electronic Resource
    URL: http://dx.doi.org/10.1063/1.478266
    Library Location Call Number Volume/Issue/Year Availability
    BibTip Others were also interested in ...
    Paper (German National Licenses)
    Fulltext
  • 3
    Electronic Resource
    Electronic Resource
    Combined photoelectron spectroscopy and ab initio study of the hypermetallic Al3C molecule (1999)
    College Park, Md. : American Institute of Physics (AIP)
    The Journal of Chemical Physics 110 (1999), S. 8980-8985 
    Details
    ISSN: 1089-7690
    Source: AIP Digital Archive
    Topics: Physics , Chemistry and Pharmacology
    Notes: The chemical structure and bonding of the hypermetallic Al3C and Al3C− species have been studied by photoelectron spectroscopy and ab initio calculations. Al3C− is found to have a planar triangular (D3h, 1A1′) structure (when averaged over zero-point vibrational modes) and Al3C is found to have a triangular distorted planar structure (C2v, 2B2) with one elongated Al–C bond. Four peaks in the photoelectron spectra of Al3C− were identified at 2.56, 2.69, 3.23, and 4.08 eV. Assignment of the observed features was made on the basis of the ab initio calculations. The experimental adiabatic electron affinity of Al3C was measured to be 2.56±0.06 eV, compared to 2.47 eV calculated at the CCSD(T)+OVGF/6-311+G(2df) level of theory. The excellent agreement between the calculated and experimental electron affinity, vibrational frequencies, and excitation energies allowed us to completely elucidate the geometrical and electronic structure of the Al3C molecule and its anion. © 1999 American Institute of Physics.
    Type of Medium: Electronic Resource
    URL: http://dx.doi.org/10.1063/1.478816
    Library Location Call Number Volume/Issue/Year Availability
    BibTip Others were also interested in ...
    Paper (German National Licenses)
    Fulltext
  • 4
    Electronic Resource
    Electronic Resource
    On the ground electronic states of copper silicide and its ions (1998)
    College Park, Md. : American Institute of Physics (AIP)
    The Journal of Chemical Physics 108 (1998), S. 5728-5732 
    Details
    ISSN: 1089-7690
    Source: AIP Digital Archive
    Topics: Physics , Chemistry and Pharmacology
    Notes: The low-lying electronic states of SiCu, SiCu+, and SiCu− have been studied using a variety of high-level ab initio techniques. As expected on the basis of simple orbital occupancy and bond forming for Si(s2p2)+Cu(s1) species, 2Πr, 1Σ+, and 3Σ− states were found to be the ground electronic states for SiCu, SiCu+, and SiCu−, respectively; the 2Πr state is not that suggested in most recent experimental studies. All of these molecules were found to be quite strongly bound although the bond lengths, bond energies, and harmonic frequencies vary slightly among them, as a result of the nonbonding character of the 2π-MO (molecular orbital) [composed almost entirely of the Si 3p-AO (atomic orbital)], the occupation of which varies from 0 to 2 within the 1Σ+, 2Πr, and 3Σ− series. The neutral SiCu is found to have bound excited electronic states of 4Σ−, 2Δ, 2Σ+, and 2Πi symmetry lying 0.5, 1.2, 1.8, and 3.2 eV above the 2Πr ground state. It is possible but not yet certain that the 2Πi state is, in fact, the "B state" observed in the recent experimental studies by Scherer, Paul, Collier, and Saykally. © 1998 American Institute of Physics.
    Type of Medium: Electronic Resource
    URL: http://dx.doi.org/10.1063/1.475982
    Library Location Call Number Volume/Issue/Year Availability
    BibTip Others were also interested in ...
    Paper (German National Licenses)
    Fulltext
  • 5
    Electronic Resource
    Electronic Resource
    Reactive dynamics for Zn(3P)+H2/D2/HD→ZnH/ZnD+H/D: Rotational populations in ZnH/ZnD products (1999)
    College Park, Md. : American Institute of Physics (AIP)
    The Journal of Chemical Physics 110 (1999), S. 229-240 
    Details
    ISSN: 1089-7690
    Source: AIP Digital Archive
    Topics: Physics , Chemistry and Pharmacology
    Notes: Using ab initio multiconfigurational potential-energy surfaces pertinent to the reaction Zn(3P)+H2→ZnH(2∑)+H and local surface tessellation and interpolation methods developed earlier, we carried out classical trajectory simulations of the title reactions, running large ensembles of trajectories with initial conditions representative of full-collision experiments. Then, using binning techniques, the ZnH/ZnD vibrational and rotational populations have been extracted. Our simulation results duplicate certain unexpected findings noted in experiments of Breckenridge and Wang [Chem. Phys. Lett. 123, 17 (1986); J. Chem. Phys. 87, 2630 (1987)]. Specifically, it is observed that the rotational profiles found for ZnH produced from H2 or from HD are nearly identical, as are the ZnD populations obtained in reactions with D2 or HD. By interrogating the progress of reactive trajectories, we have been able to identify the origin of (much of) the rotational angular momentum in the ZnH/ZnD products, which then allows us to put forth a physical model which, we believe, explains the unexpected ZnH/ZnD isotope effects in the product rotational profiles. © 1999 American Institute of Physics.
    Type of Medium: Electronic Resource
    URL: http://dx.doi.org/10.1063/1.478098
    Library Location Call Number Volume/Issue/Year Availability
    BibTip Others were also interested in ...
    Paper (German National Licenses)
    Fulltext
  • 6
    Electronic Resource
    Electronic Resource
    Two-photon ionization spectroscopy and all-electron ab initio study of LiCa (1998)
    College Park, Md. : American Institute of Physics (AIP)
    The Journal of Chemical Physics 109 (1998), S. 6655-6665 
    Details
    ISSN: 1089-7690
    Source: AIP Digital Archive
    Topics: Physics , Chemistry and Pharmacology
    Notes: Resonant two-photon ionization spectra of LiCa have been obtained from a laser vaporization, supersonic expansion source. The ground state of the molecule is confirmed to be X 2Σ+. Three band systems have been observed near 15 282, 19 310, and 22 250 cm−1 and the upper states have been assigned as 2Σ+, 2Πr, and, tentatively, 2Π. Bond lengths and vibrational frequencies are reported for 7Li40Ca for the various states as X 2Σ+: r0=3.3796(11) Å, ΔG1/2=195.2 cm−1; 2Σ+: r0=3.4275(47) Å, ΔG1/2=283.5 cm−1; 2Πr: re=3.5451(36) Å, ωe=144.5 cm−1; and 2Π: ωe=178.53(5) cm−1. The ionization energy was also measured to be 4.471(1) eV by observing the onset of one-photon ionization. Results of ab initio all-electron calculations on twelve low-lying states [2Σ+(1), 2Σ+(2), 2Σ+(3), 2Σ+(4), 4Σ+(1), 4Σ−(1), 2Π(1), 2Π(2), 2Π(3), 2Π(4), 4Π(1), and 4Π(2)] are also reported, along with results on the X 1Σ+ ground electronic state of LiCa+. The dissociation energies of LiCa(X 2Σ+) into Li(2S)+Ca(1S) and of LiCa+ (X 1Σ+) into Li+(1S)+Ca(1S) are calculated to be 0.24 and 1.20 eV respectively, and the vertical and adiabatic ionization energies of LiCa have been determined to be almost the same, 4.43 eV, at the quadratic configuration interaction, including singles and doubles with approximate triples and all correlated electrons [QCISD(T,FULL)] level of theory. © 1998 American Institute of Physics.
    Type of Medium: Electronic Resource
    URL: http://dx.doi.org/10.1063/1.477317
    Library Location Call Number Volume/Issue/Year Availability
    BibTip Others were also interested in ...
    Paper (German National Licenses)
    Fulltext
  • 7
    Electronic Resource
    Electronic Resource
    Ab initio vibration–rotation-tunneling spectra and dynamics of H2⋅F− and its isotopomers (1995)
    College Park, Md. : American Institute of Physics (AIP)
    The Journal of Chemical Physics 102 (1995), S. 1295-1305 
    Details
    ISSN: 1089-7690
    Source: AIP Digital Archive
    Topics: Physics , Chemistry and Pharmacology
    Notes: Ab initio computations of the potential energy surface (PES) of the ground electronic state of H2⋅F− have been performed as a function of the stretching F–H2 (R) and H2 rotation (θ) coordinates. Minima on the PES correspond to linear H–H–F− structures, while the transition state is T-shaped. The F− to H2 distance increases in the transition state from 2.07 to 3.10 A(ring), demonstrating strong coupling between the θ and R degrees of freedom. The vibration–rotation-tunneling spectra are calculated by diagonalizing the five dimensional Hamiltonian matrix that describes free rotation of the triatomic (three coordinates) plus the internal θ and R motions. For total angular momentum J=0, the spacing between levels in the tunneling doublets increases from 0.029 to 6.74 cm−1 as the stretching quantum number n corresponding to R motion varies from 0 to 5. The splittings increase even more strongly with the bending quantum number. For J=1, each level in the tunneling doublets is further split by Coriolis forces. K-doubling is found to be an order of magnitude smaller than the tunneling splitting. In the symmetric isotopomers D2⋅F− and T2⋅F−, the tunneling splitting drops by 3 and 4 orders of magnitude compared to H2⋅F−, and thus becomes comparable with the K-doubling for J=1. Finally, incoherent tunneling, appropriate to condensed phase environments, of the H2F− system is also treated. © 1995 American Institute of Physics.
    Type of Medium: Electronic Resource
    URL: http://dx.doi.org/10.1063/1.468918
    Library Location Call Number Volume/Issue/Year Availability
    BibTip Others were also interested in ...
    Paper (German National Licenses)
    Fulltext
  • 8
    Electronic Resource
    Electronic Resource
    Interaction of an aluminum atom with an alkaline earth atom: Spectroscopic and ab initio investigations of AlCa (1994)
    College Park, Md. : American Institute of Physics (AIP)
    The Journal of Chemical Physics 101 (1994), S. 5441-5453 
    Details
    ISSN: 1089-7690
    Source: AIP Digital Archive
    Topics: Physics , Chemistry and Pharmacology
    Notes: A spectroscopic analysis of diatomic AlCa generated by laser vaporization of a 2:1 Al:Ca metal alloy followed by supersonic expansion has been completed using resonant two-photon ionization spectroscopy. Four excited electronic states have been identified and investigated in the energy region from 13 500 to 17 900 cm−1. These are the [13.5] 2Πr, the [15.8] 2Σ, the [17.0] 2Δ3/2(?), and the [17.6] 2Δ3/2 states. From rotational analysis excited state bond lengths have been measured for three of the four excited states, and the ground state has been unambiguously determined as a 2Πr state with a weighted least squares value of the ground state bond length of r0‘ = 3.1479± 0.0010 A(ring). The ionization energy of the molecule has also been directly determined as 5.072±0.028 eV. Ab initio calculations for the potential energy curves of seven low-lying states of AlCa [X 2Πr, 2Σ+, 4Σ−, 4Πr, 2Πr(2), 2Δ, and 2Σ−] and for the X 1Σ+ ground electronic state of AlCa+ have been carried out. In agreement with experiment, 2Πr is calculated to be the ground electronic state of the neutral molecule. The dissociation energies of AlCa (X 2Πr) into Al(3s23p1,2P0)+Ca(4s2,1S) and for AlCa+ (X 1Σ+) into Al+(3s2,1S)+Ca(4s2,1S) are calculated to be 0.47 and 1.50 eV, respectively. The excited 2Σ+, 4Σ−, 4Πr, 2Πr(2), 2Δ, and 2Σ− states are calculated to lie 0.2, 0.7, 0.7, 1.1, 1.1, and 1.1 eV above X 2Πr, respectively, and the vertical and adiabatic ionization energies of AlCa have been calculated to be 5.03 and 4.97 eV, respectively.
    Type of Medium: Electronic Resource
    URL: http://dx.doi.org/10.1063/1.467333
    Library Location Call Number Volume/Issue/Year Availability
    BibTip Others were also interested in ...
    Paper (German National Licenses)
    Fulltext
  • 9
    Electronic Resource
    Electronic Resource
    Combining doubly charged cations and anions to form new species (1994)
    College Park, Md. : American Institute of Physics (AIP)
    The Journal of Chemical Physics 100 (1994), S. 5778-5784 
    Details
    ISSN: 1089-7690
    Source: AIP Digital Archive
    Topics: Physics , Chemistry and Pharmacology
    Notes: In this study we predict, based on our ab initio electronic structure calculations, the existence and relative stabilities of several new species such as H3SMgF3, H2SMgF2, and HSMgF derived from combining the geometrically metastable and electronically stable parent doubly charged ions H4S+2 and MgF−24. Although this study focuses on compounds obtained from these particular double ions, we suggest that analogous observations will be obtained when other double ions are used. Stable structures of the HSMgF, and H2SMgF2 molecules, as well as a local energy minimum and two different second-order saddle point geometries for the H3SMgF3 molecule were found. The lowest-energy stable structure is that found for H3SMgF3, which is best described as a dative adduct of H2S, MgF2, and HF, and which lies ∼570 kcal/mol below the separated-ion starting materials and ∼140 kcal/mol below the (H4S+2)(MgF−24) contact ion pair.
    Type of Medium: Electronic Resource
    URL: http://dx.doi.org/10.1063/1.467141
    Library Location Call Number Volume/Issue/Year Availability
    BibTip Others were also interested in ...
    Paper (German National Licenses)
    Fulltext
  • 10
    Electronic Resource
    Electronic Resource
    Potential energy curves of M(np 2P)⋅RG(2Π) excited states and M+⋅RG ground states (M=Li, Na; RG=He, Ne) (1994)
    College Park, Md. : American Institute of Physics (AIP)
    The Journal of Chemical Physics 100 (1994), S. 8212-8218 
    Details
    ISSN: 1089-7690
    Source: AIP Digital Archive
    Topics: Physics , Chemistry and Pharmacology
    Notes: It has been established for some time that the bond energies for any given valence pπ excited state of Group 1 (2P) and Group 2 (1,3P) metal-atom/rare-gas (M⋅RG) van der Waals complexes tend to increase with the polarizability of the RG atom. It is also known that the binding energies of the corresponding M+⋅RG ground state ions are generally greater than those of the neutral M(pπ)⋅RG excited states with the same RG atom. However, there are two stark exceptions to these trends, both involving Group 1 metal atoms and the rare gas He; Li(2p 2P)⋅He(2Π) and Na(3p 2P)⋅He(2Π), which are the focus of the present study. We have conducted ab initio calculations of the potential energy curves of M(np 2P)⋅RG(2Π) and M+⋅RG states, where M=Li, Na and RG=He, Ne. We find that the unusual behavior of the pπ Group 1 metal atom states is due to (i) the lack of M(pπ)–RG(pπ) repulsive orbital overlap in the He case, and (ii) substantial additional attraction due to correlated motion of the RG atom's electrons and the diffuse M(npπ) electron which is absent in the M+RG cases.
    Type of Medium: Electronic Resource
    URL: http://dx.doi.org/10.1063/1.466764
    Library Location Call Number Volume/Issue/Year Availability
    BibTip Others were also interested in ...
    Paper (German National Licenses)
    Fulltext
Close ⊗
This website uses cookies and the analysis tool Matomo. More information can be found here...