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In response to the COVID-19 pandemic, the Psychological Science Accelerator coordinated three large-scale psychological studies to examine the effects of loss-gain framing, cognitive reappraisals, and autonomy framing manipulations on behavioral intentions and affective measures. The data collected (April to October 2020) included specific measures for each experimental study, a general questionnaire examining health prevention behaviors and COVID-19 experience, geographical and cultural context characterization, and demographic information for each participant. Each participant started the study with the same general questions and then was randomized to complete either one longer experiment or two shorter experiments. Data were provided by 73,223 participants with varying completion rates. Participants completed the survey from 111 geopolitical regions in 44 unique languages/dialects. The anonymized dataset described here is provided in both raw and processed formats to facilitate re-use and further analyses. The dataset offers secondary analytic opportunities to explore coping, framing, and self-determination across a diverse, global sample obtained at the onset of the COVID-19 pandemic, which can be merged with other time-sampled or geographic data.

The COVID-19 pandemic has increased negative emotions and decreased positive emotions globally. Left unchecked, these emotional changes might have a wide array of adverse impacts. To reduce negative emotions and increase positive emotions, we tested the effectiveness of reappraisal, an emotion regulation strategy which modifies how one thinks about a situation. Participants from 87 countries/regions (N = 21,644) were randomly assigned to one of two brief reappraisal interventions (reconstrual or repurposing) or one of two control conditions (active or passive). Results revealed that both reappraisal interventions (vs. both control conditions) had consistent effects in reducing negative emotions and increasing positive emotions across different measures. Reconstrual and repurposing had similar effects. Importantly, planned exploratory analyses indicated that reappraisal interventions did not reduce intentions to practice preventive health behaviours. The findings demonstrate the viability of creating scalable, low-cost interventions for use around the world to build resilience during the pandemic and beyond.

A technique, based on amplitude modulation of Atomic Force Microscope (AFM) tips, in the absence of an applied bias voltage, is reported in this study. Under ambient humidity conditions, ultra-sharp n- doped silicon tips (spike radius ~1 nm) oscillating at 160–250 kHz generate raised nanostructures ~50–200 nm wide and ~2 nm high on undoped or p -doped Si (100) surfaces pretreated with certain neat organic solvents. The solvents in the present work are propan-2-ol, butan-2-ol, or toluene. AFM is used to characterize the nanostructures which are found to be stable for at least 96 h. It is suggested that mechanical stress associated with the oscillatory Hookean energy (~5–15 eV) of the tip promotes cleavage of residual solvent bonds on the surface. This bond cleavage, and the presence of surface defects, which may be critical in the formation of surface-solvent bonds (specifically Si–O–C or Si–C) to create the observed nanostructures, is discussed. The process described here to create raised nanostructures is distinctly different from all other reported techniques to date.

The adsorption mechanism for the new compound, 7-ethynyl-2,4,9-trithia-tricyclo[3.3.1.13,7]decane (7ETTD), on ultra-thin films (∼3 nm) of CdS is investigated. Multiple reflection absorption IR spectroscopy, in conjunction with inelastic electron tunneling spectroscopy, indicates that this compound forms a self-assembled monolayer adsorbed on the CdS surface via each molecule’s trithia-adamantane anchor. Conductance–voltage data are recorded for tunnel junctions of the type Al/CdS/7ETTD/Pb over a temperature range of 4 K to room temperature and they indicate that the presence of the 7ETTD layer on the CdS dramatically modifies the conductance–voltage behavior of the junctions. These measurements show that different conduction mechanisms, including tunneling and possibly hopping, are responsible for charge transfer through the junctions depending on current, temperature, and voltage. WKB fits to the data are used to determine barrier parameters (height and width) for Al/CdS/Pb junctions with and without adsorbed 7ETTD layers on the CdS. Analysis of the fits shows that tunneling occurs at low bias (less than ∼0.2 V) but, at higher bias voltages, modification of the barrier parameters alone is insufficient to account for the observed conductance changes. A frontier orbital model is invoked which does offer a plausible explanation for these conductance changes. The model assumes bias-dependent coupling between HOMO and LUMO states of the adsorbed 7ETTD and the surface states on the CdS. The present work suggests that, because of the marked effect on the conductance of CdS ultra-thin films, 7ETTD and other similar compounds may be candidates for use in molecular electronic device fabrication.

Ultrathin oxygenated amorphous CdTe (a-CdTe:O) films are prepared by rf sputtering of CdTe in a background of argon or argon/nitrogen/oxygen mixtures. Atomic force microscopy (AFM) is used to characterize the films and shows that they have an island structure typical of most sputtered thin films. However, when sufficiently low powers and deposition rates are employed during sputtering, the resulting films are remarkably smooth and sufficiently thin for use as barrier layers in inelastic electron tunneling (IET) junctions. Four terminal current–voltage data are recorded for Al/a-CdTe:O/Pb tunnel junctions and conductance–voltage curves are derived numerically. WKB fits to the conductance–voltage curves are obtained using a two-component trapezoidal plus square (TRAPSQR) model barrier potential to determine values for the tunnel barrier parameters (height, shape, and width); these parameters are consistent with AFM topological measurements and values from similar devices reported in the literature. IET spec...

In this, the second in a series of three articles, inelastic electron tunneling (IET), and Fourier transform MRAIR spectra are obtained for a series of aliphatic di-carboxylic acids and oxo-substituted aliphatic di-carboxylic acids. The acids are chosen in order to investigate the effect of the internal carbonyl group location within the molecule itself on spectral intensities. The oxo-substituted di-carboxylic acids produce a carbonyl absorption in the region 1700–1760 cm−1 for IET spectra. These are attributed to the internal carbonyl group present in these molecules, since this vibration is absent in the corresponding spectra for the non-oxo-substituted di-carboxylic acids. A comparison of MRAIR spectra for samples prepared with and without a lead cover film shows that both carbonyl, and C–H mode intensities for the MRAIR samples are attenuated to various degrees by the presence of a lead cover film depending on their location within the molecules. This indicates steric hindrance of these groups by the lead cover film, which causes the molecular backbone to be canted at the alumina surface. Evidence for this is obtained from the unusually high intensity of the asymmetric carboxylate ion stretch in the MRAIR spectra for samples with a lead cover film.

In this paper, the last in the series of three articles, inelastic electron tunneling (IET) spectra are obtained for a series of aliphatic dicarboxylic acids of increasing chain length with one of the methylene groups substituted by a carbonyl group which is not involved in bonding with the alumina surface. The effect of surface coverage on the relative intensity of the carbonyl mode is discussed. For lower surface coverages, the number of possible configurations for the adsorbed molecules increases, and in certain cases, the carbonyl group is located closer to the lead cover film thereby attenuating its intensity. The effect of changing location of the carbonyl group within the molecule (and hence, the tunnel barrier) and increasing chain length on the relative intensity of the carbonyl mode is also discussed.

In the first of a series of three articles, evidence for attenuation of the carbonyl vibrational mode intensity in inelastic electron tunneling spectroscopy (IETS), and multiple reflection absorption infrared spectroscopy (MRAIRS) is presented. The work may have considerable impact on the interpretation of IET and MRAIR spectra of certain polymers adsorbed on alumina of interest in the field of adhesion. For a better comparison between the two techniques, MRAIR spectra are recorded for compounds adsorbed on conventional oxidized aluminum mirror samples and on samples prepared with thin-film lead cover films to form planar aluminum/alumina/compound/lead structures similar to the tunnel junctions used for IETS. The compounds chosen for the study are all carboxylic acids, known to adsorb on alumina by coordinate bonding of the carboxylate anion in acid–base reactions. The acids contain non-bonding carbonyl groups on the carbon backbone of the molecules whose intensities are investigated. When the compounds are constrained by the above sample geometry, similar carbonyl attenuation is observed in both IETS and MRAIRS, but to varying degrees depending on the geometry of the adsorbed molecules. The effect, which disappears in MRAIR spectra for samples without the lead cover films, can be explained by consideration of the deformation of the molecules by the lead cover film, which results in steric hindrance of the carbonyl groups and a corresponding reduction in their activity in accordance with the orientational selection rules for both IETS and MRAIRS. This and further spectroscopic evidence for deformation of the molecules by the lead cover film is discussed.

A relatively simple and inexpensive ac signal regulator is described which facilitates constant resolution inelastic electron tunneling spectroscopy (IETS). Constant resolution is achieved by maintaining an approximately constant ac modulation voltage across IET junctions during spectral scans. The regulator circuit is based upon a field-effect transistor optoisolator with appropriate feedback control acting as a voltage comparator. It is modular in design and can easily be added in the signal path of existing IET spectrometers. A complete schematic diagram of the circuit is provided as well as a discussion on the theory of operation. IET spectra obtained from tunnel junctions with various degrees of nonlinear conductance-voltage behavior are presented with, and without, the circuit. Analysis of these spectra shows that the regulator increases the spectrometer’s signal-to-noise ratio, produces no distortion and, in the case of severely nonlinear junctions, reveals spectral features at mid to high bias, wh...

IET spectra are presented for the first time for inorganic monolayers adsorbed on artificial tunnel barriers. They are obtained from hydrolyzed triethoxysilane (TES) monolayers introduced onto ultra-thin sputtered germania films incorporated in Al/germania/TES/Pb tunnel junctions. The minimum thickness required for germania film continuity is determined to be ∼ 1.5nm using a reliable method which is described. Three techniques are then used to dope the germania surface with TES; these are by exposure to: (i) TES vapor under a dry nitrogen atmosphere, (ii) TES vapor under a water vapor/nitrogen atmosphere, and (iii) aqueous acidic hydrolyzed TES solution. Vibrational spectra obtained using (i) and (iii) are similar; in both cases strong Si H stretching and bending modes are present at approximately 2000–2200 cm −1 , and 900 cm −1 respectively. However, only very weak features due to residual CH species are present. These results confirm that the TES hydrolyses to a large degree and condenses on the germania surface. Spectra obtained using (ii) are similar to those obtained by the other two methods but also contain vibrational modes due to Si O Si stretching vibrations, which indicates that the TES not only hydrolyzes and condenses on the surface, but also polymerizes to form a hydrogenated polysiloxilane matrix. In contrast, spectra obtained for TES adsorbed on alumina using the same three techniques indicate that the TES neither hydrolyzes, condenses, nor polymerizes unless introduced from an aqueous acidic solution.

Vibrational spectra obtained using IETS and MRAIRS are presented for monolayers of pyruvic acid adsorbed on alumina, incorporated in thin film Al/alumina/pyruvic acid/Pb samples. Spectra obtained using both techniques do not exhibit a carbonyl peak, however MRAIR spectra for similar samples without a Pb cover film do. This behaviour may be attributed to interactions between the adsorbed molecules and the cover film. Possible reasons for this, and the disappearance of certain peaks in the IET spectra when Sn and Al are employed as cover films instead of Pb, are discussed.

Detailed instructions for producing and separating C60 and C70 are presented. The experiment involves elements of both physics and chemistry. After initial setup of the equipment, results are obtainable within a few hours. Additional experiments for observing physical properties of the fullerenes are suggested. A complete list of equipment is provided, with vendors and catalog numbers, for those wishing to duplicate the experiment.

Atomic force microscopy is used to image the surface relief of epitaxial Bi films grown on mica substrates. Monatomic terrace steps are readily resolved, which provide detailed information on crystal growth and defect structures. The films grow from the coalescence of isolated three-dimensional islands, however, each island grows layer-by-layer. The islands are triangular in shape and when they coalesce to form a continuous film, their structures are either in-phase, and consequently large crystallites are formed, or they are out-of-phase and defect structures are formed. The most common defects observed are twinning and stacking faults. Images showing the microscopic details of stacking faults, twinning, and grain boundaries are observed as a result of islands coalescing to form a continuous film.

An easily realized inelastic electron tunneling spectrometer (IETS) controlled by computer through an IEEE‐488 interface bus is described. Components and circuits of the system are described in detail in order to help newcomers to IETS build a research quality spectrometer on a relatively low budget. The system design is much simpler and easier to implement than others reported in the literature, and experimental results indicate that the spectrometer has comparable resolution and signal‐to‐noise ratio. Additionally, in‐house software routines offer the system considerable flexibility in spectral data manipulation, for example, background correction, numerical differentiation, and subtraction of one spectrum from another may be performed.

Ultrathin amorphous SiO2 films are radio frequency sputter deposited onto thin film gold electrodes and incorporated as the insulating barrier in metal/insulator/metal tunnel junctions of the type Au/SiO2/Pb. Inelastic electron tunneling spectra (IETS) recorded at 4.2 K reveal characteristic zero bias anomalies associated with rapid variations in the Pb density of states on either side of the superconducting gap which shows unequivocally that tunneling is the primary conduction mechanism through the junctions at this temperature. Full IET spectra reported are essentially identical to those previously recorded for similar SiO2 films on aluminum. Atomic force and scanning tunneling microscope images of the SiO2 and underlying gold films are also presented; these data confirm that the SiO2 films are sufficiently uniform and continuous for IETS.

Amorphous SiO films are prepared by radio‐frequency planar magnetron sputtering in a background of argon. Inelastic electron tunneling spectra are presented of the films incorporated in Al/SiO/Pb tunnel junctions with the aluminium films pre‐ or post‐oxidized relative to the SiO deposition stage. Both the aluminium and lead junction electrodes are evaporated in a standard oil diffusion pumped, liquid nitrogen trapped vacuum system at a base pressure of 10−7 Torr; aluminium oxidation is achieved either by admitting oxygen into the vacuum chamber or by performing a low power dc oxygen glow discharge. Spectra obtained are similar, but not identical, to those obtained for evaporated SiO films. Different types of silicon hydride species are observed depending on the environment to which the SiO films are exposed after their deposition. Possible reactions of the films with water vapor are discussed which could produce the observed hydrides which are also assigned. Reverse bias tunneling spectra provide strong e...

Inelastic electron tunneling spectroscopy (IETS) is used to record the vibrational spectra of thin films of amorphous SiOx prepared by radio‐frequency planar magnetron sputter deposition in argon. The SiOx films are incorporated as the insulating barriers in aluminium SiOx/lead tunnel junctions, with no prior or subsequent oxidation of the aluminium films. Peak assignments are presented by comparison with infrared, Raman, and neutron scattering data for bulk silica, and a plausible stoichiometry is proposed. The SiOx barriers can be considered as model glass substrates for further adsorption studies, and hence extend the analytical capabilities of IETS.

Nanoscale surface modification is reported for styrene butadiene rubber using an electrically biased conducting atomic force microscope tip. Under appropriate bias conditions, the local electric field magnitude is of the order of 10 8 ‐10 9 Vm 1 , which is sufficiently large to initiate cross-linking in the rubber. Peaklike surface features, surrounded by a circular trough and a raised ring, are created by careful and controlled retraction of the biased tip. The features’ aspect ratios can be controlled by modifying the tip retraction protocol, tip geometry, and bias voltage. Typical feature dimensions reported here vary from approximately 0.5‐10-nm high and up to several hundreds of nanometer in diameter. Although the temperature of the rubber is above the glass transition and the rubber is in a viscous state, the features are stable over a period of several days once created—which is believed to be due to cross-linking of the rubber during feature formation. Modeling of the electric field distribution in the vicinity of the tip is presented, which strongly supports the assertion that the resulting nonuniform electric field induces nanostructure formation and initiates cross-linking. A mechanism is proposed whereby source material is redistributed in the proximity of the tip/surface region to form the observed features.

A robust technique, based on vertical (z-lift) manipulation of a negatively biased oscillating atomic force microscope cantilever, is developed which creates raised columnar nanostructures with high aspect ratios (up to 40nm high/150nm wide) on amorphous CdS thin films. The nanostructures’ height (8–40nm) is proportional to z-lift of the tip and correlates with CdS film thickness. An in-house modified electric force microscopy is used to record the associated surface charge distribution which is found to be opposite to that of the tip.

Inelastic electron tunnelling spectra have been obtained for plasma-polymerized polyvinylacetate, polyethylacrylate, polyacrylic acid, polymethylmethacrylate and polyacrylonitrile on hydrated aluminium oxide. Spectra of plasma-polymerized polyvinyl-acetate and polymethylmethacrylate are very similar to those of conventional free radical polymers. All polymers exhibit spectral peaks at about 1440 cm−1 and 1600 cm−1 which are due to the carboxylate anion, and this indicates that ester groups are cleaved on the oxide to produce ionic attractions at the interface which are advantageous for adhesive bonding.