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Abstract: Surface-enhanced infrared absorption (SEIRA) experiments revealed that the chain length and evaporation rate of alkane deposition solvents altered 4-fluorobenzoic acid (4FBA) adsorption. 4FBA did not dissociate in the multilayer with the fast-evaporating n-pentane deposition solvent. However, with n-hexane and heavier solvents, the evaporation rate was slow enough to allow significant formation of 4-fluorobenzoate ions (4FBI) in the multilayer. Strong intermolecular attractions were present with heavier deposition solvents as evidenced by the incorporation of n-heptane into the 4FBI multilayer. This work will apply to many synthetic, biological, and environmental areas involving the interaction of metal nanostructures with oxygenated or halogenated hydrocarbons. [ABSTRACT FROM AUTHOR]

Abstract: SERS, SEIRA, and DFT calculations showed silver nanoparticles can stimulate C–H⋯O hydrogen bonding in 4-fluorobenzoate ion/n-heptane multilayers. SERS/DFT demonstrated that 4-fluorobenzoic acid (4FBA) adsorbed as a 4-fluorobenzoate (4FBT) monolayer on nanosilver. Ionization of 4FBA to 4FBT occurred in the multilayer when 4FBA was deposited in n-heptane onto nanosilver. Frequency shifts in SEIRA bands of 4FBT COO stretch and n-heptane CH bend modes illustrated a change in the degree of C–H⋯O hydrogen bonding as more 4FBT/n-heptane was adsorbed to the multilayer. This work will influence many research areas such as sensors formed from thin organic layers on metal nanoparticles. [Copyright &y& Elsevier]

Toddlerhood is a period where issues of autonomy and control in parent-child relationships become particularly intense. In response to these challenges, some parents adopt controlling practices, whereas others are more autonomy supportive. However, research has yet to examine prenatal orientations that foreshadow specific controlling or autonomy-supportive parental practices in toddlerhood and children's socioemotional functioning. In particular, literature on early childhood socialization lacks sufficient evidence on the effects of the controversial controlling practice of parental conditional positive regard. To increase our knowledge on these issues, we examined reports provided by Israeli Jewish mothers during their first pregnancy ( N = 294), at 18-month postpartum ( N = 226), and when the child was 42 months old ( N = 134). To control for child temperament, both parents reported 8-month postpartum ( N = 235) on infant temperament dispositions, which may act as precursors of later socioemotional functioning. Structural equations modeling revealed that a general prenatal maternal orientation to use conditional regard as a socialization practice predicted mothers' use of the specific practices of conditional positive and negative regard with toddlers, which then predicted internalizing problems when children reached the age of 42 months. Additionally, a general prenatal orientation toward autonomy-supportive parenting predicted mothers' perspective taking with toddlers, which then predicted children's prosocial behavior at 42 months. The effects emerged also after controlling for infants' temperamental dispositions toward negative emotionality and positive affect. Findings underlie the potential role of prenatal orientations toward conditional regard and autonomy support that, when later transform into specific early parenting practices, may serve as early markers of child socioemotional adjustment. (PsycInfo Database Record (c) 2024 APA, all rights reserved).