scholarly journals Laboratory search for spin-dependent short-range force from axionlike particles using optically polarizedHe3gas

2013 ◽  
Vol 87 (1) ◽  
Author(s):  
P.-H. Chu ◽  
A. Dennis ◽  
C. B. Fu ◽  
H. Gao ◽  
R. Khatiwada ◽  
...  
Keyword(s):  
Short Range ◽  
Short Range Force ◽  
Range Force

Lattice Vibrations of the Cooperites PdO and PtS

1989 ◽  
Vol 44 (3) ◽  
pp. 169-172 ◽  
Author(s):  
G. Kliche
Keyword(s):  
Force Field ◽  
Vibrational Spectra ◽  
Short Range ◽  
Lattice Vibration ◽  
Covalent Bonding ◽  
Lattice Vibrations ◽  
Vibration Frequencies ◽  
Short Range Force ◽  
Range Force ◽  
Good Agreement

The vibrational spectra of the cooperite type compounds PdO and PtS (space group P42/mmc - D4h9, Z = 2) are analyzed. Good agreement between experimental and calculated lattice vibration frequencies is obtained using a force field which includes short-range force constants only. This demonstrates a highly covalent bonding character of the cooperites.

LOCAL DIPOLE FIELD CONTRIBUTIONS TO BOND-STRETCHING SILICON–HYDROGEN VIBRATIONAL MODES ON FLAT AND VICINAL Si(111) SURFACES

1997 ◽  
Vol 04 (05) ◽  
pp. 891-896 ◽  
Author(s):  
H.-Y. YANG ◽  
G. LUCOVSKY
Keyword(s):  
Short Range ◽  
Vicinal Surfaces ◽  
Flat Surfaces ◽  
Coupled Mode ◽  
Dipole Interactions ◽  
Short Range Force ◽  
Bond Stretching ◽  
Hydrogenated Amorphous ◽  
Range Force ◽  
Better Than

Bond-stretching frequencies for bonded-H (and D) on flat and vicinal Si(111) surfaces have been calculated using a model that includes (i) short range valence forces and (ii) dynamic effects due to dipole–dipole interactions. Dipole–dipole interactions have been calculated exactly for flat surfaces, and for vicinal surfaces off-cut in the [Formula: see text] and [Formula: see text] directions terminated respectively by monohydride, Si–H, and dihydride, Si–H 2, bonding at the step edges. Using short range force constants and effective charges obtained from isolated Si–H and Si–H 2 stretching modes in hydrogenated amorphous Si, a-Si:H, as input parameters, the calculated coupled mode frequencies are in excellent agreement with experiment, i.e. using 5 empirical parameters, 16 frequencies in the range of 1500–2150 cm-1 are fit to better than 0.14%, or ±2–3 cm-1.

A New Isothermal Equation of State for Solids

2009 ◽  
Vol 64 (1-2) ◽  
pp. 54-58
Author(s):  
Quan Liu
Keyword(s):  
Equation Of State ◽  
Critical Analysis ◽  
Short Range ◽  
Rare Gas ◽  
Volume Data ◽  
Volume Dependence ◽  
Short Range Force ◽  
Good Accordance ◽  
Isothermal Equation ◽  
Range Force

A new isothermal equation of state (EOS) for solids is derived by starting from the theory of lattice potential and using an analytical function for the volume dependence of the short-range force constant. A critical analysis of the isothermal EOSs: Murnaghan EOS, Vinet EOS, and the new EOS derived here, is presented by investigating the pressure-volume data for rare gas solids, metals and minerals. It is found that the results obtained from the new EOS are in good accordance with the corresponding values obtained from the Vinet EOS and with experimental data for all the solids up to very large compressions. On the other hand, the Murnaghan EOS is less successful at high pressure in most cases.

Molecular Model Calculations of Pair–Modes in Alkali Halides

1974 ◽  
Vol 52 (16) ◽  
pp. 1492-1501 ◽  
Author(s):  
R. W. Ward ◽  
B. P. Clayman
Keyword(s):  
Short Range ◽  
Nearest Neighbor ◽  
Molecular Model ◽  
Alkali Halides ◽  
Nearest Neighbors ◽  
Local Mode ◽  
Relevant Parameter ◽  
Model Calculations ◽  
Short Range Force ◽  
Range Force

The molecular model, developed by Jaswal for [100] aligned impurity pairs, has been extended to account for [110] aligned pairs and used to study U center (H−H− and D−D−) pairs in KCl and (Cl−Cl− and Na+Na+)-induced pair–modes in the gap of KI. In this model the impurity ions in the pair and their nearest neighbors are allowed to vibrate while the rest of the lattice is held fixed. For [110] and [100] aligned pairs, this gives 12- and 17-ion molecules respectively. The potential energy is treated in the rigid ion approximation with short range forces between the nearest neighbors only. After the single relevant parameter of the model, the nearest neighbor force constant, is fitted to the U center local mode frequency, the model can account for the experimentally observed frequencies and polarizations of the three U center pairs in KCl. Similarly, after fitting to the single ion Cl− gap mode at 77 cm−1 in KI, the model predicts 3 infrared active pair–modes whose frequencies are in close agreement with experiment. In KI:Na+, where no single ion resonance has been observed, the calculated results suggest that the absorption lines are due to [110] aligned Na+ ions, with a large softening of the short range force constants occurring around the defect. The KI:Br− and NaCl:F− systems are also considered.

A Short-Range Force

2005 ◽  
Vol 44 (8) ◽  
pp. 1303-1305
Author(s):  
B. G. Sidharth
Keyword(s):  
Short Range ◽  
Short Range Force ◽  
Range Force
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