Characterization of Pd/Y multilayers with B4C barrier layers using GIXR and X-ray standing wave enhanced HAXPES

Pd/Y multilayers are high-reflectance mirrors designed to work in the 7.5-11 nm wavelength range. Samples, prepared by magnetron sputtering, are deposited with or without B₄C barrier layers located at the interfaces of the Pd and Y layers to reduce interdiffusion, which is expected from calculating the mixing enthalpy of Pd and Y. Grazing-incident X-ray reflectometry is used to characterize these multilayers. B₄C barrier layers are found to be effective in reducing Pd-Y interdiffusion. Details of the composition of the multilayers are revealed by hard X-ray photoemission spectroscopy with X-ray standing wave effects. This consists of measuring the photoemission intensity from the samples by performing an angular scan in the region corresponding to the multilayer period and an incident photon energy according to Bragg's law. The experimental results indicate that Pd does not chemically react with B nor C at the Pd-B₄C interface while Y does react at the Y-B₄C interface. The formation of Y-B or Y-C chemical compounds could be the reason why the interfaces are stabilized. By comparing the experimentally obtained angular variation of the characteristic photoemission with theoretical calculations, the depth distribution of each component element can be interpreted.

Opening of a Peierls gap in BaVS3 probed by V L3 edge resonant inelastic x-ray scattering

V L3 edge resonant inelastic x-ray scattering measurements performed on high quality BaVS3 single crystals reveal that the intra-t2g dd excitations close to the elastic peak are suppressed below the metal-insulator transition induced by the Peierls instability. The depletion of electronic states close to the Fermi level represents a direct observation of the opening of a charge gap inside the t2g manifold.

BaVS3 probed by V L edge x-ray absorption spectroscopy

Polarization dependent vanadium L edge x-ray absorption spectra of BaVS(3) single crystals are measured in the four phases of the compound. The difference between signals with the polarizations E perpendicular to c and E is parallel to c (linear dichroism) changes with temperature. Besides increasing the intensity of one of the maxima, a new structure appears in the pre-edge region below the metal-insulator transition. More careful examination brings to light that the changes start already with pretransitional charge density wave fluctuations. Simple symmetry analysis suggests that the effect is related to rearrangements in the E(g) and A(1g) states, and is compatible with the formation of four inequivalent V-sites along the V-S chain.

Ground state of the quasi-1D compound BaVS3 resolved by resonant magnetic x-ray scattering

Resonant magnetic x-ray scattering near the vanadium L2,3-absorption edges has been used to investigate the low temperature magnetic structure of high quality BaVS3 single crystals. Below T(N)=31  K, the strong resonance revealed a triple-incommensurate magnetic ordering at the wave vector (0.226   0.226   ξ) in hexagonal notation, with ξ=0.033. The azimuthal-angle dependence of the scattering signal and time-dependent density functional theory simulations indicate an antiferromagnetic order within the ab plane with the spins polarized along a in the monoclinic structure.

Collective magnetic excitations in the spin ladder Sr14Cu24O41 measured using high-resolution resonant inelastic x-ray scattering

We investigate magnetic excitations in the spin-ladder compound Sr_{14}Cu_{24}O_{41} using high-resolution Cu L_{3} edge resonant inelastic x-ray scattering (RIXS). Our findings demonstrate that RIXS couples to two-triplon collective excitations. In contrast to inelastic neutron scattering, the RIXS cross section changes only moderately over the entire Brillouin zone, revealing high sensitivity also at small momentum transfers, allowing determination of the two-triplon energy gap as 100 +/- 30 meV. Our results are backed by calculations within an effective Hubbard model for a finite-size cluster, and confirm that optical selection rules are obeyed for excitations from this spherically symmetric quantum spin-liquid ground state.

Density-functional study of the cycloaddition of acrylonitrile on the Si(100) surface

Using a density functional approach, we have explored the cycloaddition of acrylonitrile on the Si(100) surface. The buckling of the surface dimers characteristic for the (2x1) reconstructed surface is shown to favor structures with a dipolar moment such as the resonant form of acrylonitrile with cumulative double bonds. The bond of acrylonitrile via a single C atom is a possible intermediate leading to the nitrile structure of the adsorbed molecule.

Bortner type A scores and eight basic emotions for survivors of ventricular fibrillation and left ventricular failure during acute myocardial infarction

We examined Bortner scores for behavioral patterns and eight basic emotional dimensions named by Plutchik for patients with acute myocardial infarction who survived ventricular fibrillation and left ventricular failure. There were 70 patients, 48 men and 22 women ages 26 to 69 yr. (M = 54, SD = 8), admitted to the coronary care unit within 24 hours of the onset of a long-lasting chest pain. Six patients survived an episode of ventricular fibrillation that occurred within 24 to 48 hours after their admission. 15 patients developed left ventricular failure and were in Killip Classes II and III. Patients with acute myocardial infarction and left ventricular failure had mean Bortner scores significantly lower than others with acute myocardial infarction and were classed as Type B behavior. There was no difference in Bortner scores between patients with ventricular fibrillation and others with acute myocardial infarction. Patients with acute myocardial infarction and left ventricular failure scored significantly higher on Timid than others with acute myocardial infarction. Patients with acute myocardial infarction and ventricular fibrillation scored significantly lower on Depressed and higher on Distrust than other patients with acute myocardial infarction. Our findings suggest that patients with ventricular fibrillation and low scores on Depressed have good hospital prognosis. They are more critical and tend to reject people and ideas more than patients with acute myocardial infarction. This study suggests that the way in which patients with acute myocardial infarction react to their infarction, in terms of eight basic emotions and test patterns, is dependent on the complications of myocardial infarction.

Responses to Bortner's scale and the eight basic emotions by patients with acute coronary heart disease at hospital admission and discharge

We examined the prevalence of Type A behavior indicated on Bortner's scale and the Emotion Profiles of Plutchik in 190 patients, 134 men and 56 women (M age = 50 yr., SD = 9) with acute coronary heart disease at hospital admission and discharge. Type A classification was significantly more common for patients with acute coronary heart disease (75.5% versus 65%) than for the control group. Patients with acute coronary heart disease scored lower on Distrust and Dyscontrolled than the control group. Patients with unstable angina had significantly higher mean scores on Bortner's scale than patients with acute myocardial infarction and recurrent myocardial infarction at hospital discharge. Patients with recurrent myocardial infarction scored lower on Distrust and higher on Timid than patients with unstable angina at hospital admission and discharge. This research suggests that Type A behavior and some emotions are associated with acute coronary heart disease. There was a difference in scores on the Emotions Profiles and scores on Type A behavior in relation to type of acute coronary heart disease. The addition of counseling for Type A behavior to standard cardiac counseling was suggested for reduction in scores on Type A behavior.

Relationship of eight basic emotions with age, sex, education, satisfaction of life needs, and religion

Personality scores of Croatian men and women by age, occupation, education, satisfaction of life needs, and religion were examined. 842 men and 242 women whose mean age was 42 yr. (SD, 8) represented manual labor, clerical work, and management. Employees were administered the Emotions Profile Index and a test of Life Needs Satisfaction. The Croatian women scored lower on Distrustful and Dyscontrol than the Croatian men and higher on Depression and Gregarious. Scores on Aggression, Depression, and Gregarious varied across age groups. The Reproduction scores of sociable and affectionate were significantly higher for managers and persons with university education. The religious employees scored higher on Depression than nonreligious persons. The Reproduction scores were significantly positively associated with all needs satisfaction scores. The Destruction scores (Aggression, Depression) were significantly negatively associated with most life needs satisfactions. The present analysis suggests men and women from Croatian groups have different personality profiles. Correlations of emotional scores with ages, occupations, education, life needs satisfaction, and religion could help in modification toward positive emotional dimensions.

Association of scores for Type A behavior with age, sex, occupation, education, life needs satisfaction, smoking, and religion in 1084 employees

The associations of Type A or B behavior with age, sex, occupation, education, life needs satisfaction, smoking, and religion were studied. 242 women and 842 men, ages 21 to 64 years, (M age 42 +/- 8 yr.), completed the Bortner scale and rated on a 5-point scale their life needs satisfaction. Information on age, occupation, education, cigarette smoking, and religion were obtained from each subject. Scores for Type A and Type B behavior patterns in different age groups were very similar. Scores on Type A behavior were significantly more common in women than men. Type A behavior scores were identified in a larger proportion of managers, clerks, and in persons with university education than in manual workers and persons with only primary and secondary education. There was no difference between smokers and non-smokers and religious and nonreligious scorers. There was no difference in ratings for life needs satisfaction between persons identified as having scores on Type A and Type B behavior. The present analyses enhance our understanding of Type A behavior as related to age, sex, occupation, education, and life needs satisfaction in a Croatian sample.

Type A/B behavior and eight basic emotions in 1084 employees

We examined the prevalence of Type A/B behavior and Emotion Profiles in 1084 employees. This report focused on the relationship between Type A behavior and eight basic emotion dimensions. Of the 1084 subjects 710 (65%) scored as Type A and 374 (34.5%) as Type B. The mean Bortner scores for all subjects were 182.8 (SD = 33.7), scores on emotional dimensions for Incorporation and Reproduction were high, and intensities for Ejection and Destruction were low; mean scores on other emotions were normal. Significant differences between Type A and Type B scores were found on six emotional dimensions. Subjects classified as Type A had ratings lower on trustful, controlled, and timid and higher on aggressive, distrustful, and uncontrolled than did persons classified as Type B. There were no differences between Type A and Type B scores on the emotion dimensions of Reproduction and Deprivation. Our data suggest multiple emotional components may comprise the Type A behavior pattern. This is important for behavioral counseling programs and early preventive efforts which could be aimed at reducing the intensity of Type A behaviors.