Library

X
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
    Electron spin resonance investigations of 11B12C, 11B13C, and 10B12C in neon, argon, and krypton matrices at 4 K: Comparison with theoretical results (1989)
    College Park, Md. : American Institute of Physics (AIP)
    The Journal of Chemical Physics 90 (1989), S. 690-699 
    Details
    ISSN: 1089-7690
    Source: AIP Digital Archive
    Topics: Physics , Chemistry and Pharmacology
    Notes: The first spectroscopic study of the diatomic radical BC is reported which confirms previous theoretical predictions of a 4∑− electronic ground state. The nuclear hyperfine interactions (A tensors) obtained for 11B, 10B, and 13C from the electron spin resonance (ESR) measurements are compared with extensive ab initio CI calculations. The BC molecule is one of the first examples of a small high spin radical for such an in-depth experimental–theoretical comparison. The electronic structure of BC obtained from an analysis of the nuclear hyperfine interaction (hfi) is compared to that obtained from a Mulliken-type population analysis conducted on a CI wave function which yields Aiso and Adip results in good agreement with the observed values. The BC radical was generated by the laser vaporization of a boron–carbon mixture and trapped in neon, argon, and krypton matrices at 4 K for a complete ESR characterization. The magnetic parameters (MHz) obtained for 11B13C in solid neon are: g(parallel) =2.0015(3); g⊥ =2.0020(3); D(zfs)=1701(2); 11B: ||A(parallel)|| =100(1); ||A⊥|| =79(1); 13C: ||A(parallel)|| =5(2) and ||A⊥|| =15(1). Based on comparison with the theoretical results, the most likely choice of signs is that all A values are positive.
    Type of Medium: Electronic Resource
    URL: http://dx.doi.org/10.1063/1.456148
    Library Location Call Number Volume/Issue/Year Availability
    BibTip Others were also interested in ...
    Paper (German National Licenses)
    Fulltext
  • 2
    Electronic Resource
    Electronic Resource
    The generation of 12C31P and 13C31P by reactive laser vaporization for rare gas matrix electron spin resonance studies: Comparison with ab initio theoretical calculations (1988)
    College Park, Md. : American Institute of Physics (AIP)
    The Journal of Chemical Physics 88 (1988), S. 3441-3450 
    Details
    ISSN: 1089-7690
    Source: AIP Digital Archive
    Topics: Physics , Chemistry and Pharmacology
    Notes: The 12C31P and 13C31P diatomic radicals have been generated by the laser vaporization reaction between carbon and phosphorus which were pressed into a pellet to form the laser target. This method is applicable to a wide range of nonmetallic systems for generating new reactive intermediates which cannot be done with more conventional approaches. The radicals were isolated in neon and argon matrices at 4 K for detailed ESR investigations. The magnetic parameters (MHz) for neon were: g(parallel)=2.0009(3); g⊥=1.9902(3); A(parallel)(31P)=145.0(3); A⊥(31P)=−269.0(2); A(parallel)(13C)=580.0(3); and A⊥(13C)=422.0(3). The argon A and g tensors were virtually indistinguishable from these neon results. Extensive ab initio theoretical calculations were conducted for CP which yielded nuclear hyperfine A values in close agreement with the experimental results. Valence orbital spin populations extracted from the calculated CI wave functions are compared with those determined directly from the ESR hyperfine parameters for 13C and 31P. The observed g shift for CP agreed with the gas phase spin–rotation constant and indicates the presence of a low lying 2πr state that has not been previously observed.
    Type of Medium: Electronic Resource
    URL: http://dx.doi.org/10.1063/1.454713
    Library Location Call Number Volume/Issue/Year Availability
    BibTip Others were also interested in ...
    Paper (German National Licenses)
    Fulltext
  • 3
    Electronic Resource
    Electronic Resource
    Laser vaporization/rare gas matrix-isolation electron spin resonance studies of PdH+2, PdD+2, PdH, and PdD: Theoretical investigation of PdH+2 (1990)
    College Park, Md. : American Institute of Physics (AIP)
    The Journal of Chemical Physics 92 (1990), S. 2721-2732 
    Details
    ISSN: 1089-7690
    Source: AIP Digital Archive
    Topics: Physics , Chemistry and Pharmacology
    Notes: The reactive laser vaporization of palladium metal in the presence of H2(g) has been used to generate and trap neutral and charged palladium hydride radicals in neon and argon matrices for electron spin resonance investigations. The radicals identified are: 0PdH+2, 105PdH+2, 0PdD+2, 105PdD+2, 0PdH, 0PdD, 105PdH, and 105PdD. The electron spin resonance results prove that the H atoms are equivalent in PdH+2 but it cannot be determined for certain whether a highly bent 2A1 ground state complex or a linear 2Σ state is being observed, although the evidence seems to favor the 2A1 state. The observed nuclear hyperfine properties (A and g tensors) are best accounted for by assigning the unpaired electron predominantly to 4d2z/5s orbitals on the metal in PdH+2 with only about 3% of the spin density on each H atom. Electron spin resonance results for PdH constitute the first observations for a diatomic metal hydride radical trapped in a neon matrix. The magnetic parameters (MHz) for 105PdH+2 in a neon matrix at 4 K are: g⊥=2.568(2); g(parallel)(approximately-equal-to)1.92; A⊥(105Pd)=−713(2); A(parallel)(105Pd)=−688(15); A⊥(H)=45(1). Multireference SCF (MCSCF) and configuration interaction (CI) calculations were conducted for PdH+2 to calculate the energies and gross population distributions in the lowest-lying electronic states. The lowest of these, the 2A1 state, has a calculated stabilization energy of 9.3 kcal/mol relative to Pd+(4d9)+H2.
    Type of Medium: Electronic Resource
    URL: http://dx.doi.org/10.1063/1.458580
    Library Location Call Number Volume/Issue/Year Availability
    BibTip Others were also interested in ...
    Paper (German National Licenses)
    Fulltext
  • 4
    Electronic Resource
    Electronic Resource
    Laser vaporization generation of PdCH3, 105PdCH3, and Pd13CH3 for electron spin resonance neon matrix study at 4 K (1990)
    College Park, Md. : American Institute of Physics (AIP)
    The Journal of Chemical Physics 92 (1990), S. 6463-6468 
    Details
    ISSN: 1089-7690
    Source: AIP Digital Archive
    Topics: Physics , Chemistry and Pharmacology
    Notes: The Pd12CH3, Pd13CH3, and 105Pd12CH3 radicals have been generated by reactive laser vaporization and isolated in neon matrices at 4 K for electron spin resonance (ESR) investigation. Apparently no previous monomethyl metal radical has been characterized by ESR despite the importance of such species as reactive intermediates. These results allow an experimental description of the electronic structure in the valence region to be obtained. A direct electronic structure comparison between PdH and PdCH3 is also presented. A significant amount of s/d hybridization on Pd is observed which agrees with earlier calculations on the bonding in Pd(CH3)2. The magnetic parameters (MHz) for PdCH3 in neon matrices are: g⊥=2.273(1); for 105Pd, A⊥=−946(2), A(parallel)=−987(20); for H, ||A||=13(1); and for 13C, ||A||=10.2(4).
    Type of Medium: Electronic Resource
    URL: http://dx.doi.org/10.1063/1.458326
    Library Location Call Number Volume/Issue/Year Availability
    BibTip Others were also interested in ...
    Paper (German National Licenses)
    Fulltext
  • 5
    Electronic Resource
    Electronic Resource
    The generation and electron spin resonance characterization of 63,65Cu12CH2 and 63,65Cu13CH2 in neon matrices (1989)
    College Park, Md. : American Institute of Physics (AIP)
    The Journal of Chemical Physics 91 (1989), S. 4587-4592 
    Details
    ISSN: 1089-7690
    Source: AIP Digital Archive
    Topics: Physics , Chemistry and Pharmacology
    Notes: The first ESR (electron spin resonance) results are reported for a metal–methylene radical. The CuCH2 molecule was generated by trapping the products of the pulsed laser vaporization of copper in the presence of cyclopropane in neon matrices at 4 K. A second generation procedure involved the laser vaporization of elemental carbon and copper in the presence of H2(g). The unpaired electron in CuCH2 was found to occupy primarily the carbon p orbital which was perpendicular to the C2v molecular plane. This electronic distribution confirms the 2B1 ground state assignment predicted by previous theoretial calculations. The neon matrix magnetic parameters (MHz) were: g⊥=2.000(3); g(parallel)=2.0027(3); 63Cu: A(parallel)=303(1); A⊥=306(1); H:||A(parallel)||=66.6(3); ||A⊥|| =43.1(3) and 13C@B:||Aiso||=124.3(5).
    Type of Medium: Electronic Resource
    URL: http://dx.doi.org/10.1063/1.456747
    Library Location Call Number Volume/Issue/Year Availability
    BibTip Others were also interested in ...
    Paper (German National Licenses)
    Fulltext
  • 6
    Electronic Resource
    Electronic Resource
    Electronic ground state assignment for O+4B: Neon matrix electron-spin resonance investigation (1989)
    College Park, Md. : American Institute of Physics (AIP)
    The Journal of Chemical Physics 91 (1989), S. 4423-4424 
    Details
    ISSN: 1089-7690
    Source: AIP Digital Archive
    Topics: Physics , Chemistry and Pharmacology
    Notes: The O+4 radical cation has been generated by two different methods and trapped as an isolated ion in neon matrices at 4 K for electron-spin resonance (ESR) investigation. The O+4 species is a potentially important atmospheric ion for which little experimental or theoretical information is available. These ESR results indicate that the electronic ground state of O+4 is a nonlinear quartet (S=3/2) with the three unpaired electrons occupying primarily 2p(π) orbitals. The fine structure-parameters obtained from an analysis of the ESR spectrum are D=1.875(5) and E=0.0350(5) cm−1 . The isotopic ions16,17 O+4 were also generated but the 17 O hfs could not be fully analyzed because of the large number of overlapping hyperfine lines.
    Type of Medium: Electronic Resource
    URL: http://dx.doi.org/10.1063/1.456777
    Library Location Call Number Volume/Issue/Year Availability
    BibTip Others were also interested in ...
    Paper (German National Licenses)
    Fulltext
  • 7
    Electronic Resource
    Electronic Resource
    Neon matrix ESR investigation of 12C+2 and 13C+2 : Confirmation of a 4Σ−g ground electronic state (1988)
    College Park, Md. : American Institute of Physics (AIP)
    The Journal of Chemical Physics 88 (1988), S. 7348-7356 
    Details
    ISSN: 1089-7690
    Source: AIP Digital Archive
    Topics: Physics , Chemistry and Pharmacology
    Notes: The 12C+2 and 13C+2 cation radicals have been isolated in neon matrices by the photoionization of C2(g) generated by the laser vaporization of thin carbon disks. A new procedure of supporting and thermally outgassing such targets for laser vaporization ESR studies in rare gas matrices is described. The ESR results confirm the 4Σ−g ground electronic state assignment for C+2 and provide a valence orbital electronic structure characterization based on the 13C hyperfine structure (hfs). The ESR lines are extremely narrow for a high-spin powder sample and an intense off-angle or "extra'' absorption feature exibits unusual hfs. Normally forbidden (ΔMS〉1) transitions were detected at low magnetic fields. The magnetic parameters for 13C+2 in a neon matrix at 4 K are: D=3668(3) MHz; g⊥ =2.0018(5); g(parallel) =2.0023(5); ||A(parallel)|| =99.4(8) MHz; and ||A⊥|| =95.2(5) MHz.
    Type of Medium: Electronic Resource
    URL: http://dx.doi.org/10.1063/1.454346
    Library Location Call Number Volume/Issue/Year Availability
    BibTip Others were also interested in ...
    Paper (German National Licenses)
    Fulltext
  • 8
    Electronic Resource
    Electronic Resource
    Rare gas matrix ESR investigations of 12CH3 63,65CuF, 13CH3 63,65CuF, H63,65CuF, and D63,65CuF generated by reactive laser vaporization (1988)
    College Park, Md. : American Institute of Physics (AIP)
    The Journal of Chemical Physics 88 (1988), S. 524-532 
    Details
    ISSN: 1089-7690
    Source: AIP Digital Archive
    Topics: Physics , Chemistry and Pharmacology
    Notes: A new experimental procedure for conducting reactive laser vaporizations is described and applied to the generation of the previously unreported copper radicals, 13CH3CuF, 12CH3CuF, HCuF, and DCuF, for rare gas matrix ESR investigations. Laser vaporization was conducted on a thin film of reactant condensed on the copper metal surface. The g and A tensors for these are compared with other small copper radicals in order to determine electronic structure and bonding trends. The neon magnetic parameters (MHz) for 13CH363CuF are: g(parallel) =1.965(1), g⊥ =2.3626(3); A(parallel)(63Cu) =3076(2), A⊥(63Cu) =2993(1); A(parallel)(19F) =94(1), A⊥(19F) =68(1); A(parallel)(13C) =19(1), A⊥(13C) 〈3. The H quartet hfs for CH3CuF was resolved on the perpendicular transitions, having an A value of 9.3(3) MHz. For H63CuF, the neon results (MHz) are: g(parallel) =1.975(1); g⊥ =2.4075(4); A(parallel)(63Cu) =2826(3), A⊥(63Cu) =2717(1); A(parallel)(19F) =127(2), A⊥(19F) =94(1); A(parallel)(H) =61(3), and A⊥(H) =29(1) MHz.
    Type of Medium: Electronic Resource
    URL: http://dx.doi.org/10.1063/1.454179
    Library Location Call Number Volume/Issue/Year Availability
    BibTip Others were also interested in ...
    Paper (German National Licenses)
    Fulltext
  • 9
    Electronic Resource
    Electronic Resource
    ESR investigation of the cubane radical cation (C8H8+) in neon matrixes at 4 K (1987)
    s.l. : American Chemical Society
    Journal of the American Chemical Society 109 (1987), S. 5521-5523 
    Details
    ISSN: 1520-5126
    Source: ACS Legacy Archives
    Topics: Chemistry and Pharmacology
    Type of Medium: Electronic Resource
    URL: http://dx.doi.org/10.1021/ja00252a036
    Library Location Call Number Volume/Issue/Year Availability
    BibTip Others were also interested in ...
    Paper (German National Licenses)
    Fulltext
  • 10
    Electronic Resource
    Electronic Resource
    Laser sputtering generation of B2 for ESR matrix isolation studies: comparison with ab initio CI theoretical calculations (1987)
    s.l. : American Chemical Society
    Journal of the American Chemical Society 109 (1987), S. 3521-3525 
    Details
    ISSN: 1520-5126
    Source: ACS Legacy Archives
    Topics: Chemistry and Pharmacology
    Type of Medium: Electronic Resource
    URL: http://dx.doi.org/10.1021/ja00246a004
    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...