Search results for "Topic shift"
showing 10 items of 18 documents
The Loss of Grammatical Gender and Case Features Between Old and Early Middle English: Its Impact on Simple Demonstratives and Topic Shift
2017
AbstractIn this paper we examine the relation between the loss of formal gender and Case features on simple demonstratives and the topic shifting property they manifest. The examination period spans between Old English and Early Middle English. While we argue that this loss has important discourse-pragmatic and derivational effects on demonstratives, we also employ the Strong Minimalist Hypothesis approach (Chomsky 2001) and feature valuation, as defined in Pesetsky & Torrego (2007), to display how their syntactic computation and pragmatic properties have come about. To account for the above innovations yielding the Early Middle Englishϸe(‘the’), we first discuss the formal properties o…
Complete basis set B3LYP NMR calculations of CDCl3solvent's water fine spectral details
2008
The assignment of singlet at 1.55 ppm and the 1:1:1 triplet at 1.519 ppm to H2O and HOD in the 400 MHz 1H NMR spectrum of CDCl3 solvent were supported by complete basis set (CBS) GIAO-B3LYP calculated chemical shift and the CBS B3LYP estimated 2J(D,H) spin–spin coupling constant (SSCC). The CBS fitting of B3LYP/cc-pCVxZ and B3LYP/pcJ-n predicted SSCC values, the accurate value of 2J(D,H) = − 1.082 ± 0.030 Hz of HOD in chloroform-d1 and the H/D isotopic shift of 0.0307(1) ppm were reported for the first time. The agreement between CBS B3LYP predicted chemical shift, spin–spin values and experiment was good. Copyright © 2008 John Wiley & Sons, Ltd.
Infrared spectroscopy of ruthenium tetroxide and high-resolution analysis of the ν3 band
2015
Abstract RuO 4 is a heavy tetrahedral molecule which has practical uses for several industrial fields. Due to its chemical toxicity and the radiological impact of its 103 and 106 isotopologues, the possible remote sensing of this compound in the atmosphere has renewed interest in its spectroscopic properties. New, higher resolution FTIR spectra have been recorded at room temperature, using an isotopic pure sample of 102 RuO 4 and a sample with all stable isotopes present in natural abundance. We reinvestigate here the strong ν 3 stretching fundamental region and perform new assignments and effective Hamiltonian parameter fits for the five main isotopologues ( 99 RuO 4 , 100 RuO 4 , 101 RuO …
Symmetry: Friend or foe?
1999
While symmetry in molecules or supramolecular complexes is desirable from the design point of view and affords simpler NMR spectra, the study of symmetrical species by NMR is often subject to ambiguities resulting from signal degeneracy. In this paper we shall discuss different ways of breaking symmetry in order to obtain additional structural information by NMR.
Topics in atomic hyperfine structure and isotope shift
1976
Recent developments in atomic hyperfine structure and isotope shift are discussed under the following aspects: (i) Precise evaluation of nuclear moments and isotopic change of nuclear charge radii by quantitative computation of atomic structure or by calibration of the atomic constants through results from electronic and mesic X-ray spectroscopy. (ii) How to apply spectroscopic methods to nuclei far off stability. (iii) What can be learned from a systematic investigation of long isotopic chains.
Isotope shift and hyperfine structure measurements at the242f Am fission isomer
1996
Istope shift and hyperfine structure measurements have been performed for the242fAm fission isomer with target production rates of only a few per second. The method is based on resonance ionization spectroscopy (RIS) in a buffer gas cell with radioactive decay detection of the ionization process (RADRIS). A relative isotope shift ratioX exp=IS242f,241/ IS243,241=41.7±0.9 has been measured for the 500.02 nm transition corresponding to a nuclear parameter Λ242f,241=5.4±0.3 fm2. The analysis of the quadrupole moment based on the deformed Fermi-model of the nuclear charge distribution including second order corrections results inQ 20=38.2 ±1.4( −0.8 +0.4 )model eb. The measurement of the hyperf…
Hyperfine structure and isotope shift investigations in $^{202-222}$Rn for the study of nuclear structure beyond Z = 82
1986
The hyperfine structure (hfs) and isotope shift (IS) in the isotopic chain of the radioactive element radon have been studied for the first time. The measurements were carried out by collinear fast-beam laser spectroscopy at the mass separator facility ISOLDE at CERN. The IS between 16 isotopes in the mass range 202≦A≦222 and the hfs of 7 odd-A isotopes were determined in the transitions 7s [3/2]2-7p [5/2]3 (745 nm) of Rn I. The nuclear spins and moments, as well as the observed inversion of the odd-even staggering for218–222Rn, can be associated with the effects of octupole instability around N=134.
From radop to laser spectroscopy and back
1985
The paper reviews some techniques in optical spectroscopy of short-lived nuclei, their results regarding nuclear moments and isotopic shift, and their relation to the work of Professor K. Sugimoto.
Determination of spin, magnetic moment and isotopic shift of neutron rich205Hg by optical pumping
1975
Neutron rich205Hg (T 1/2=5.2 min) was produced and on-line mass separated at the ISOLDE facility at CERN. The polarization achieved by optical pumping via the atomic line (6s 21 S 0↔6s6p 3 P 1,λ=2 537A) was monitored by theβ decay asymmetry. Hyperfine structure and isotopic shift of the205Hg absorption line was determined by Zeeman scanning. In addition a magnetic resonance was performed on the polarized205Hg nuclei in the atomic ground state. The results are: $$I(^{205} Hg) = \tfrac{1}{2}$$ (confirmed);μ I (205Hg)=0.5915 (1)μ N (uncorrected for diamagnetism); isotopic shiftδv204/205=v(205Hg)-v(204Hg)=−1.8 (1) GHz.μ I and IS are discussed briefly in the frame of current literature.
DETERMINATION OF NUCLEAR GROUND STATE PROPERTIES FAR FROM STABILITY BY OPTICAL PUMPING
1973
The possibilities of determining nuclear spin, moments and variation in charge volume by optical pumping of on line masseparated isotopes are described for the example of the isotopic chain lY1Hg-205Hg. The variation in nuclear charge volume (6 ) along this chain and in particular its abrupt change for the lightest Hg-isotopes, indicating a phase transition in nuclear structure, are discussed. 1. Introduction. - This talk is based on expe- riments (I), (2), (3) performed recently by a visiting team (*) at the ISOLDE facility at CERN with the members : J. Bonn, G. Huber, H.-J. Kluge, U. Kopf, L. Kugler, J. Rodriguez, and E. W. Otten. The investigation of the hyperfine structure (hfs) and iso…