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  • 1
    Electronic Resource
    Electronic Resource
    College Park, Md. : American Institute of Physics (AIP)
    The Journal of Chemical Physics 104 (1996), S. 923-934 
    ISSN: 1089-7690
    Source: AIP Digital Archive
    Topics: Physics , Chemistry and Pharmacology
    Notes: The absorption spectrum of the van der Waals molecule KAr has been recorded between 12 870 and 13 040 cm−1 by means of high-resolution laser excitation spectroscopy in a supersonic jet expansion. About 1600 molecular absorption lines could successfully be assigned to the rovibrational structure of the electronic transition A 2Π←X 2Σ+ of 39KAr. In addition, a few absorption lines due to the isotopomer 41KAr have been detected. Spectroscopic parameters have been obtained for vibrational levels 0...3 of X 2Σ+ and 6...11 of A 2Π. Additional experimental information was provided by observing the spectral distribution of the fluorescence. The interatomic potentials of the X 2Σ+ and the A 2Π states have been derived from the experimental data by means of a fully quantum-mechanical approach using suitable analytical functions. Our final results for equilibrium distance Re and well-depth De are 5.404(5) A(ring) and 40.1(6) cm−1 for X 2Σ+, 3.37(3) A(ring) and 405(15) cm−1 for A 2Π1/2, and 3.34(3) A(ring) and 427(15) cm−1 for A 2Π3/2. In addition, we could deduce qualitative information on the B 2Σ+ interaction potential from our experimental data yielding Re=7.10 A(ring) and De=23 cm−1 as preliminary values. © 1996 American Institute of Physics.
    Type of Medium: Electronic Resource
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  • 2
    Electronic Resource
    Electronic Resource
    College Park, Md. : American Institute of Physics (AIP)
    The Journal of Chemical Physics 114 (2001), S. 3535-3545 
    ISSN: 1089-7690
    Source: AIP Digital Archive
    Topics: Physics , Chemistry and Pharmacology
    Notes: Line shift coefficients, line broadening coefficients, and line narrowing coefficients have been measured in the ν1+3ν3 band of acetylene using a diode laser system operating at 788 nm and a multipass Herriot absorption cell. Experimental data have been obtained for 20 lines of the P and R branches broadened by N2, O2, air, and the rare gases He, Ne, Ar, Kr, and Xe. The observed line shapes could successfully be reproduced by employing Galatry and Rautian functions which include the phenomenon of Dicke narrowing. Our results for the line broadening coefficients are in good agreement with the values reported previously for other vibrational bands. Thus, the present work confirms the vibrational independence of the broadening coefficients. On the other side, we observed a clear dependence of the narrowing coefficients on rotation in a vibrational transition of acetylene for the first time. In addition, the line center frequencies have been determined with improved accuracy. © 2001 American Institute of Physics.
    Type of Medium: Electronic Resource
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  • 3
    Electronic Resource
    Electronic Resource
    College Park, Md. : American Institute of Physics (AIP)
    The Journal of Chemical Physics 115 (2001), S. 7892-7896 
    ISSN: 1089-7690
    Source: AIP Digital Archive
    Topics: Physics , Chemistry and Pharmacology
    Notes: The spin-rotation coupling constant γ has been determined to be −0.15(6)⋅10−3 cm−1 for vibrational levels v=0, 1, and 2 of the X 2Σ+ state of 7LiAr by means of an analysis of the high-resolution absorption spectrum due to the A←X transition in the 670–677 nm region. All rovibrational levels of the X 2Σ+ state have been observed, and improved values have been obtained for the spectroscopic parameters of vibration and rotation. In addition, the dispersed fluorescence A→X has been recorded by populating selectively a particular rovibrational level of the A state. Using all experimental data, an improved X 2Σ+ interaction potential has been determined for 7LiAr, which is provided in the form of an analytical Hartree-Fock-Dispersion function. © 2001 American Institute of Physics.
    Type of Medium: Electronic Resource
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  • 4
    Electronic Resource
    Electronic Resource
    College Park, Md. : American Institute of Physics (AIP)
    The Journal of Chemical Physics 114 (2001), S. 3035-3045 
    ISSN: 1089-7690
    Source: AIP Digital Archive
    Topics: Physics , Chemistry and Pharmacology
    Notes: The absorption spectrum of the LiAr molecule has been recorded with high resolution using a supersonic beam and applying the method of laser-induced fluorescence. Altogether, about 1400 absorption lines due to the transitions A 2∏←X 2∑ and B 2∑←X 2∑ of the two isotopomers 7Li40Ar and 6Li40Ar could successfully be assigned. The spectroscopic parameters of vibration and rotation, of spin-orbit splitting, and of λ-type doubling have been obtained for vibrational levels 5–10 of A 2∏ and 0–3 of B 2∑. Using the observed rovibrational energies as input data the interatomic potentials of both electronic states have been determined in form of analytical functions by means of a fully quantum-mechanical method of approach. For the equilibrium values we get Re=2.50(8) Å, De=957(30) cm−1 for A 2∏ and Re=6.24(5) Å, De=33.8(1.0) cm−1 for B 2∑. © 2001 American Institute of Physics.
    Type of Medium: Electronic Resource
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  • 5
    Electronic Resource
    Electronic Resource
    College Park, Md. : American Institute of Physics (AIP)
    The Journal of Chemical Physics 88 (1988), S. 5396-5407 
    ISSN: 1089-7690
    Source: AIP Digital Archive
    Topics: Physics , Chemistry and Pharmacology
    Notes: The absorption spectrum of the van der Waals molecule NaKr due to the transition X 2Σ→A2Π has been observed with high resolution using a tunable single-mode cw dye laser and producing the molecules by means of supersonic expansion. About 600 lines due to the most abundant Kr-isotope Kr84 have been analyzed. The spectroscopic parameters of molecular rotation, of fine structure splitting and of λ-type doubling have been obtained for the vibrational levels v'=10⋅⋅⋅14 of the A 2Π state and for the level v‘=0 of the X 2Σ state. The experimental positions of the band origins of the vibrational transitions are in satisfactory agreement with the results of model potential calculations. The equilibrium distances of the X 2Σ and of the A 2Π state of NaKr84 have been determined to be 4.919(7) and 3.02(9) A(ring), respectively. For the well depth we obtain values of (69±4), (790±60), and (750±60) cm−1 for X 2Σ, A 2Π1/2, and A 2Π3/2, respectively.
    Type of Medium: Electronic Resource
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  • 6
    Electronic Resource
    Electronic Resource
    College Park, Md. : American Institute of Physics (AIP)
    The Journal of Chemical Physics 94 (1991), S. 5865-5874 
    ISSN: 1089-7690
    Source: AIP Digital Archive
    Topics: Physics , Chemistry and Pharmacology
    Notes: We have extended our previous laser spectroscopic investigation of the AΠ–XΣ transition of the van der Waals molecule NaKr84. Our experimental data consist now of about 1300 absorption lines and of the spectral intensity distribution of the fluorescence light. Spectroscopic parameters have been derived for the vibrational states 0,...,2 of the XΣ state and 7,...,14 of the AΠ state. The interatomic potentials of the XΣ and the AΠ states have been determined in a fully quantum-mechanical approach using analytical HFD or Tang–Toennies functions. For the equilibrium distance and the well depth we obtain 4.918(4) A(ring), 68.4(5) cm−1 for XΣ and 3.03(4) A(ring), 3.05(4) A(ring) and 795(25) cm−1, 760(20) cm−1 for AΠ1/2 and AΠ3/2, respectively.
    Type of Medium: Electronic Resource
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  • 7
    Electronic Resource
    Electronic Resource
    Oxford, UK; Malden, USA : Munksgaard International Publishers
    Experimental dermatology 13 (2004), S. 0 
    ISSN: 1600-0625
    Source: Blackwell Publishing Journal Backfiles 1879-2005
    Topics: Medicine
    Notes: Abstract:  Molecular analysis of solid malignant tumors has suggested multilineage progression of genetically unstable subclones during early stages of tumorigenesis as a common mechanism of tumor cell evolution. We have investigated whether multilineage progression is a feature of cutaneous T-cell lymphoma (CTCL). To identify individual tumor cell subclones, we determined the pattern of mutations within microsatellite DNA obtained from multiple histomorphologically confined tumor cell nests of mycosis fungoides (MF) and lymphomatoid papulosis (LyP) lesions. Tumor cells were isolated by laser microdissection, and allelotypes were determined at microsatellite markers D6S260, D9S162, D9S171, D10S215, TP53.PCR15, and D18S65. Nine cases of MF and one patient with anaplastic large cell lymphoma (ALCL) originating from LyP were analyzed at 277 different microdissected areas obtained from 31 individual lesions. Three specimens of cutaneous lichen planus microdissected at 26 areas served as the control tissue. Microsatellite instability in microdissected tissue [MSI(md-tissue)] was detected in tumor tissues of all CTCL patients. One hundred and fifty-seven of 469 analyzed polymerase chain reaction (PCR) amplifications contained mutated microsatellite alleles (34%). In lichen planus, MSI(md-tissue) was seen in only four of 76 PCR products (5%) (P 〈 0.0001). The distribution of allelotypes in tumor cells from different disease stages was consistent with multilineage progression in five MF cases, as well as in the LyP/ALCL patient. Our results suggest that CTCL may evolve by multilineage progression and that tumor subclones in MF can be detected in early disease stages by mutation analysis of microsatellite DNA obtained from multiple microdissected areas.
    Type of Medium: Electronic Resource
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  • 8
    Electronic Resource
    Electronic Resource
    Springer
    The European physical journal 275 (1975), S. 5-10 
    ISSN: 1434-601X
    Source: Springer Online Journal Archives 1860-2000
    Topics: Physics
    Notes: Abstract The lifetime of the first excited 4P 1/2-state of potassium has been determined to be τ=27.3(3) nsec by investigating the intensity of the scattered resonance light of the potassiumD 1-line as a function of a magnetic field. From this result the absorption oscillator strength of theD 1-line of potassium could be deduced to bef=0.326(4).
    Type of Medium: Electronic Resource
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  • 9
    ISSN: 1434-601X
    Source: Springer Online Journal Archives 1860-2000
    Topics: Physics
    Notes: Abstract A modification of the atomic beam magnetic resonance method for investigation of the hyperfine structure of excited atomic states will be described. Radiofrequency transitions between the hyperfine structure niveaus of the excited state, which are unequally populated by circularly polarized light, are detected by observing the resulting change in population number of the hyperfine structure niveaus of the ground state using magnetic deflection in an inhomogeneous field and additional radiofrequency transitions in the ground state as analyzers. As an application the hyperfine structure of the excited 42 P 3/2-state of K39 has been investigated in an almost strong magnetic field of about 65 G with a constant frequency of the applied radiofrequency field of 125.50 Mc/s. The analysis of the radiofrequency signal of the excited state detected as a change in the amplitude of a radiofrequency transition in the ground state yielded the valuesA=(6.10±0.25) Mc/s andB=(1.8±1.2) Mc/s for the hyperfine structure constants of the 42 P 3/2-state of K39. Further possibilities for observing signals of the excited state with the apparatus used in this experiment are also discussed.
    Type of Medium: Electronic Resource
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  • 10
    Electronic Resource
    Electronic Resource
    Springer
    The European physical journal 315 (1984), S. 123-124 
    ISSN: 1434-601X
    Source: Springer Online Journal Archives 1860-2000
    Topics: Physics
    Notes: Abstract An additional factor of (n/N)3 has to be included in the usual procedure for deducing the change in mean square nuclear charge radii from optical field isotope shift measurements, n and N being the principal and the relativistic quantum number of the s-electron respectively. This correction amounts to about 8 % for heavy atoms as for example Hg leading to better agreement between results from optical field isotope shift measurements and from electronic and muonic X-ray data.
    Type of Medium: Electronic Resource
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