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Using the normal incidence x-ray standing wave technique as well as low energy electron microscopy we have investigated the structure of quasi-freestanding monolayer graphene (QFMLG) obtained by intercalation of antimony under the $\left(6\sqrt{3}\times6\sqrt{3}\right)R30^\circ$ reconstructed graphitized 6H-SiC(0001) surface, also known as zeroth-layer graphene. We found that Sb intercalation decouples the QFMLG well from the substrate. The distance from the QFMLG to the Sb layer almost equals the expected van der Waals bonding distance of C and Sb. The Sb intercalation layer itself is mono-atomic, flat, and located much closer to the substrate, at almost the distance of a covalent Sb-Si bond length. All data is consistent with Sb located on top of the uppermost Si atoms of the SiC bulk.

Metal complexes at surfaces and interfaces play a prominant role in many areas of modern technology, including catalysis, sensors, and organic electronics. An important aspect of these interfaces is the possible exchange of the metal center, because this reaction can drastically alter the properties of the metal complex and thus of the interface. Here, we demonstrate that such metal exchange reactions are indeed possible and can proceed already at moderate temperatures even in the absence of solvents. Specifically, we studied the redox transmetalation of a monolayer of lead(II)-tetraphenylporphyrin (PbTPP) with copper from a Cu(111) surface under ultrahigh-vacuum (UHV) conditions using multiple surface-sensitive techniques. Temperature dependent X-ray photoelectron spectroscopy (XPS) reveals that the Pb/Cu exchange starts already below 380 K and is complete at 600 K. The identity of the reaction product, CuTPP, is confirmed by mass spectrometric detection in a temperature-programmed reaction (TPR) experiment. Scanning tunneling microscopy (STM) sheds light on the adsorbate structure of PbTPP at 300 K and uncovers the structural changes accompanying the transmetalation and side-reactions of the phenyl substituents. Moreover, individual free Pb atoms are observed as a product of the metal exchange. Our study suggests that surfaces functionalized with metal complexes may consist of other species than intended under operation conditions, which often involve elevated temperatures.

Organic/inorganic hybrid interfaces play a prominent role in organic (opto)electronics, heterogeneous catalysis, sensors, and other current fields of technology. The performance of the related devices and processes depends critically on the nature and strength of interfacial interaction. Here, we use the molecular isomers naphthalene (Nt) and azulene (Az) on the Ag(111) and Cu(111) surfaces as model systems that cover different bonding regimes from physisorption to chemisorption. Az also serves as a model for nonalternant molecular electronic materials and for topological 5–7 defects in graphene. The interaction energies are determined from the quantitative analysis of temperature-programmed desorption data. On both surfaces, Az binds more strongly than Nt, with zero-coverage desorption energies (in kJ/mol) of 120 for Az/Ag and 179 for Az/Cu, compared to 103 for Nt/Ag and 114 for Nt/Cu. The integrated experimental energies are compared with adsorption energies from density-functional theory (DFT) calculations, which include van der Waals contributions using four different correction schemes for the PBE functional: (1) the DFT-D3 scheme with Becke–Johnson damping, (2) the vdWsurf correction based on DFT-TS, (3) a many-body dispersion correction scheme, and (4) the D3surf scheme. Differences in the performance of these methods are discussed. Periodic energy decomposition analysis reveals details of the surface chemical bond and confirms that Az/Cu forms a chemisorptive bond, while the other systems are physisorbed. The variation of the adsorbate–substrate interaction with the topology of the π-electron system and the type of surface can be employed to modify the interface properties in graphene-based and organic electronic devices.

INTRODUCTIONThe title quote "My Filipina is from Ghana was provided to me by Jan Trost. He overheard two women in Israel talking about their respective home care workers. The quote calls attention to the increased number of women serving as home care workers and providing care to children and to the elderly. These workers frequently are from less economically developed countries that in increasing number migrate to more highly economically developed countries. For the most part four major emigration flows can be identified: from Southeast Asia to the Middle and Far East, from Africa to Europe, from East to West in Europe, and from Central and South America to North America There is also a significant migration from the Philippines to both the United States and Canada.Many migrants are women seeking economic opportunities that will enable them to provide for themselves as well as for their families back in the home countries. This migration, global in scope, is representative of the female underside of globalization where females from Third World countries leave their homes to provide what have been traditional domestic services-care for the elderly and child care-for their First World female counterparts who live liberated lives like men. At the same time, other women in the Third World countries are affected by this migration in that they often assume the responsibility of taking care of family members of those migrated women.Women in the United States as well as in other countries of the Western World have seen a dramatic change in their lives over the last fifty years. Ever increasingly as a consequence of feminist movements as well as major changes in economic structures that demand the necessity of two incomes to maintain a middle class and more affluent life style, more and more women are now in the paid labor force. Yet, the previous gender inequalities especially in terms of the division of domestic labor, including child care and care of the elderly remain for the most part still in the women's sphere. For these women the time spent in occupational employment leaves little time for traditional domestic work. For the affluent, this time slack has been taken up largely by other lower status (wage earning) women of whom a significant number of whom are from Third World countries.Journalist Polly Toynbee (2003) observes the implications of this phenomenon for two sets of women-those from the First World the others from the Third World. She observes that affluent women in Western countries that have all the accoutrements of wealth-Armani suits, Gucci briefcases, etc.-participate in the oppression of Third World women. These low-paid women have in effect assumed the responsibilities of domestic labor that have been discarded by their professional counterparts. Toynbee concludes that these domestic working women make it possible for their professional counterparts to live liberated lives like men.Hochschild and Ehrenreich (2003) in their edited collection on Global Women bring together a discussion of migrant women who occupy different occupational positions-nannies, maids, and sex workers to document the feminization of this new economy. They see a global "care chain" being set into motion. This care chain is a series of personal links among people living across the globe based on the paid or unpaid work of caring. Hochschild (2003: 34) elucidates that the first link in this global care chain is an older daughter from a poor family in a Third World country taking care of her younger siblings. The second link is the daughter's mother taking care of children of a mother who works, the third link, as a nanny taking care of children in a First World country.Hochschild notes that just as there is a "brain drain" where rich countries gain the labor of talented and highly trained individuals from poorer countries there is this parallel "care drain." She observes "that there is a major trend in which women who normally care for the young, the old, and the sick in their own poor countries move to care for the young, the old, and the sick in rich countries, whether as maids and nannies or as day-care and nursing-home aides" (Hochschild: 2003: 35). …

Changes Within the Young Family" were discussed. These were: "Images of Woman's Action" (Dr. C. Carisse); "Early and Enforced Marriages" (Dr. W. Dumon); "The Sexual Image of Marriage Through History" (Dr. B. I. Murstein); "Marital Expectations Discrepancies Between Ideals and Realities" (Dr. C. Safilios-Rothschild); "The Dual Career Family" (Drs. Rhona and Robert Rapoport); "Some Alternative Types of Family Structure" (Dr. M. Young); "Economic Behavior of Young Families" (Dr. T. Walter).3