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Cu(In,Ga)Se 2 absorbers were investigated by surface photovoltage (SPV) in the Kelvin probe and fixed capacitor arrangements before and after deposition of CdS or In 2 S 3 buffer layers as well as before and after deposition of ZnO window layers. Effects such as passivation of surface states, partial electron transfer from ZnO into In 2 S 3 , decrease of the ideality factor after deposition of ZnO and slow electron transfer through In 2 S 3 were demonstrated. The results show that SPV measurements open opportunities for dedicated studies of charge separation at hetero-junctions between ordered and disordered semiconductors.

The room temperature deposition of PTCDA on hydrogen passivated Si(1 1 1), as a function of evaporation temperature and dosing time, has been studied by STM. At low evaporation temperature, 200 °C, clusters with an average size of 3.5 nm are formed on the surface. The mobility of the small clusters is so high, even at room temperature, that most of the clusters are trapped at surface defects. By increasing the evaporation temperature to 230 °C, larger clusters are formed which have lower mobility. The growth process is identified as a Volmer-Weber mechanism. On increasing the evaporation temperature further to 250 °C, crystals with dendritic shape are formed with an average size of 150 nm. The terraces of the crystal are formed with the (1 0 2) basal plane of the α-phase. Molecular resolution on the terrace also allows us to identify the molecular mechanism involved in the growth of the dendritic crystals.

The surface recombination velocity at clean and modified Si(1 0 0)2×1, Si(1 1 1)-1×1 and Si(1 1 1)-7×7 surfaces was studied with the pulsed photoluminescence technique. High resolution electron energy loss spectroscopy and low energy electron diffraction were employed to correlate the surface recombination velocity to the chemical bonds at the surface and the surface morphology. Passivation of surface dangling bonds by the chemisorption of water and maleic anhydride shows that the surface dangling bonds are not recombination active. In contrast, we observe that the introduction of oxygen or carbon atoms into Si backbonds causes the generation of non-radiative recombination centres.

We show that, counterintuitively, maleic anhydride on Si(1 0 0) surfaces adsorbs on inter-row sites. Our first principles simulations establish that this site is preferred for coverages of less than 1/8 ML. In simulations of scanning tunnelling images we establish also, that the corrugation is enhanced by more than 0.5 A, if a single molecular state contributes to the tunnelling current. The combined evidence of images and simulations allows the conclusion that experiments in fact reveal the geometry of single molecular wavefunctions.

The defect transformation under growth of submonolayer oxides on silicon surfaces is studied in situ on reconstructed Si(100)-2×1 and Si(111)-7×7 surfaces and on hydrogenated Si surfaces of Si nanocrystallites. The methods of the quenching of the photoluminescence of bulk c-Si due to surface recombination and of the infrared free carriers absorption in mesoporous Si are used. It is shown that dangling bonds at Si–Si dimers are not recombination active. Non-radiative surface defects are generated during the earliest stages of oxidation. The generation of hole traps is tightly related to an increase of physisorbed H 2 O at hydrogenated Si surfaces during the native oxidation.

The formation of electronic states in the fundamental gap at the maleic anhydride/Si(1 0 0)-2×1 interface has been studied with photoluminescence (PL) measurements and high resolution electron energy loss spectroscopy (HREELS). We observe that the room temperature adsorption of maleic anhydride on Si(1 0 0)-2×1, where the organic molecules are mainly in a di-σ coordination, results in a gap state density D it =1.8(2)×10 12 eV −1 cm −2 which is slightly lower than determined for the clean Si(1 0 0)-2×1 surface. After heating maleic anhydride/Si(1 0 0)-2×1 to 1115 K, the gap state density has increased to 6.4(6)×10 12 eV −1 cm −2 which we relate to the formation of silicon carbide structures on the silicon surface.

Management of the violent patient begins with rapid, systematic global assessment of the behavior followed by attention to its most likely cause. The evaluation should focus on the issue of provocation in the pre-assault phase; the goal-directedness of the assaultive behavior in the assault phase; and the response of the patient after the attack. Organic and psychodynam ic causes as well as drug-related violence are discussed. The author gives recommendations for assessment and management of assault on the general hospital ward and in the emergency room, and discusses violence directed toward physicians.

The control of undesirable behaviors by aversive techniques under the label “aversion therapy” has become an increasingly prominent behavior therapy. The attention given to these techniques is a measure of resistance of disorders such as sexual deviations to more traditional therapies. Although effective in the animal laboratory, aversive control applied clinically may not be entirely appropriate. Some theoretical and practical draw-backs to aversion therapy are discussed, and an alternative is suggested in the use of positive behavioral control. In illustration, two cases of transvestism are presented.

Summary Problems encountered in the psychotherapeutic management of severely disturbed patients are examined. Although “human interest” has its role to play in the care of chronic psychotic patients, this paper attempts to delineate and reaffirm the necessity for specific diagnosis and treatment techniques which rely on the concepts of patient and therapist adaptations. “Adaptive psychotherapy” is defined, its theoretical basis outlined, its goals and principles described and clinical vignettes of its techniques are presented.