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Interaction between p-toluenesulfonic acid (pTSA) and water is studied at −20 °C in a CCl4 matrix. In CCl4 water exists as monomers with restricted rotational motion about its symmetry axis. Additionally, CCl4 is transparent in the hydrogen-bonded region; CCl4 thus constitutes an excellent ambient thermal energy matrix isolation medium for diagnosing interactions with water. Introducing pTSA-nH2O gives rise to two narrow resonances at 3642 cm–1 and at 2835 cm–1 plus a broad 3000–3550 cm–1 absorption. In addition, negative monomer symmetric and asymmetric stretch features relative to nominally dry CCl4 indicate that fewer water monomers exist in the cooled (−20 °C) acid solution than in room-temperature anhydrous CCl4. The negative peaks along with the broad absorption band indicate that water monomers are incorporated into clusters. The 3642 cm–1 resonance is assigned to the OH-π interaction with a cluster containing many water molecules per acid molecule. The 2835 cm–1 resonance is assigned to the (S-)O–...

Periodic static ab initio studies are conducted of hexagonal bilayer ice (HBL) and basal layers of ice-1h adsorbed on graphene using the model BLYP-D in CRYSTAL09. Eight high-symmetry periodic forms of HBL are optimized, of which four have lower energy; their electronic binding energy to graphene is ∼1.6 kcal/mol per abutting H2O. Optimized geometries have the property of maximizing the occurrence of a certain O-H-C alignment motif. One lattice is selected for more detailed study. Its 2-D shear translation potential energy surface is found to have barrier heights in two zigzag directions of ∼140 cal/mol per abutting H2O. A second hexagonal bilayer can be added and the electronic binding energy drops from ∼1.7 to ∼1.0 kcal/mol per abutting H2O. For ice-1h monolayer adsorbed on graphene, a proton-ordered form in which half of the O's nearest the graphene carry a proton pointing toward graphene is preferred over proton-ordered forms in which either all or none of those O's have H's pointing toward graphene. Cohesive energy for two-layer ice-1h on graphene is 0.66 kcal/mol of H2O higher than for HBL, supporting experimental evidence that the graphene+HBL isomer is more stable. However, the HBL and two-HBL structures are unstable or at best metastable with respect to four layers of ice-1h.

The properties of the hydroperoxide anion, HOO(-), in water play a key role in many biological systems and industrial processes. However the dynamics of HOO(-) and its solvation shell are largely unknown. We have undertaken an ab initio molecular dynamics study of aqueous HOO(-) at ambient temperature in liquid water. Two solvation structures for the hydroperoxide anion account for 90% or more of the configurations in a 25 ps NVT run at 300 K: these have four hydrogen bond donors to the terminal oxygen atom of HOO(-) and either one or two hydrogen bond donors to its middle oxygen atom. The H of HOO(-) is essentially always a donor in an H-bond to a water molecule. Two structures with three donors to the terminal O and either one or two at the middle O are also important. A set of five NVE runs totaling 74 ps found considerable variability in the proportions of time spent in each type of solvation pattern. Mean lifetimes of these patterns ranged from 54 to 109 fs, after which the complexes were observed to transform into different, sometimes less favorable structures. Analysis of the electronic structure associated with different solvation patterns indicates that a traditional Lewis-type picture of hydrogen bonding at the middle oxygen and non-Lewis behavior at the terminal oxygen coexist in aqueous HOO(-). The non-Lewis character of the terminal oxygen is compared to similar observations of the oxygen in the hydrated hydroxide ion from previous ab initio molecular dynamics of OH(-)(aq).

This paper reports on the Interrupted Career Group, a therapy group for individuals whose professional and personal lives have drastically changed due to psychiatric illness and whoseattempts toresumeacareer orothermeaningfulactivities havebeenunsuccessful. Thirty-two personswith interruptedcareers wereasked to specifyand pursuea vocational, educational, or volunteer track that integrated previous skills and activities with their present life situation and psychiatric limitations. They were also encouraged to discuss feelings of envy, shame, inferiority, rage, and humiliation associated with their interruption or activated in their new pursuits. Twenty-two of the participants effected change by utilizing the group to discuss feelings and efforts connected to resuming an integrated track. Such changes were seen equally in vocational/educational/volunteer activities and emotional functioning, or more in emotional functioning than in vocational/educational/volunteer activities. Ten participants did not show change; they were too psychiatrically disabled, lacked adequate motivation, or were unable to process affects related to actual pursuit of changes and integration. An interactive group process focusing on feelings of shame, envy, rage, inferiority, and humiliation related to experiences of an interrupted career can contribute to improved emotional and vocational functioning. (H ARVARDREVPSYCHIATRY2001;9:234‐43.) Professionalswhobecomepsychiatricallyilloftenfindthemselves unable to meet their previous high standards of vocational performance and achievement. What follows can be described as an “interrupted career”—a temporary or permanent inability to participate professionally in regular vocational tasks and contexts, with accompanying unemployment. Although job loss and unemployment have usually been associated with layoff due to economic fluctuations, company restructuring, or other factors less related to individual competence, job loss due to psychiatric illness is di

In this paper we will discuss some quite simple H spaces with a number of remarkable properties. These properties make the spaces useful in the factorization of loop spaces on the one hand [23] and pivotal in understanding the unstable development of v 2 periodic homotopy on the other [12].