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Notes: Infrared spectra are reported for thin films of deuterated microporous amorphous ice formed at 12 K and saturated with absorbed molecular hydrogen. This paper focuses on both the influence of the surface-bound H2 on the absorption bands of the OD groups that dangle from the micropore surfaces and the behavior of the induced infrared bands of the stretching mode of H2 itself. Both structural changes and the relaxation of ortho-H2 to para-H2 are apparent from variations in the observed spectra with time and temperature. A reasonably detailed interpretation of the complex spectral behavior has been possible through simulation of spectra for H2 interacting with the surface of amorphous ice clusters generated previously in a classical trajectory study of the cluster growth through the accumulation and relaxation of individual water molecules. Potential minima were calculated with respect to H2 coordinates on the cluster surface and a qualitative interpretation of adsorbate–surface bonding provided via the partitioning of the H2⋅⋅D2O interactions into relatively weak van der Waals interactions, and stronger electrostatic interactions between the H2 quadrupole and the H2O dipole and quadrupole. The net binding of H2 to the surface is dominated by several van der Waals interactions with neighboring D2O molecules, but in most of the calculated minima, H2 also forms a single electrostatic bond to a surface molecule. While such electrostatic bonds provide only a small fraction of the binding energy, they appear to influence strongly the observed spectra. Observed H2-induced shifts in the dangling OD bands appear to be caused by electrostatic bonding of H2 to a D atom of a dangling OD and a significant fraction of the H2 intensity is proposed to originate from H2 molecules which are electrostatically bonded to dangling oxygen atoms on the surface. Calculations (which do not contain adjustable parameters) reproduce quite well several features of the measured spectra, including the splitting of the dangling OD band, the shift of this band due to binding of H2, and the frequency and the width of the H2 band.

Notes: Abstract In the former socialist countries the relation of philosophy to social reality, as shaped by the political interests of the State, must be considered for each particular case with a view to the historical dynamics of its own development. The Polish case is not typical in this regard — it was determined by the failure of forced sovietization at the institutional, cultural level and the maintenance of Poland's traditional contacts with Western European culture. In this regard Polish universities played an important role since they preserved ‘normal’ structures of academic activity. Philosophy in Poland has been marked by three currents which managed to rebuff the advances of Marxism. Best known among them is the Lwów-Warsaw school of logic and analytic philosophy. Its contribution is especially important in the methodology of philosophical inquiry and the style of responsible philosophical discourse. Though not a bed of political opposition the school's members mounted a ‘spiritual opposition’ to Marxism, especially during the Solidarity period. Catholic philosophy, as represented by the Catholic University of Lublin (KUL), has been and remains a completely independent force in Eastern and Central Europe. Doctrinally, Catholic philosophy in Poland has been divided between a more traditional, dated Thomism and the more progressive circles in Cracow where Western European philosophy, especially phenomenology, existentialism, and hermeneutics, has been influential (the significance of Józef Tischner and Karol Wojtyla, now Pope Jean Paul II). The third major current, centered in Cracow, is the phenomenology of Roman Ingarden, whose influence is manifest in a style of philosophizing that has attracted professional philosophers as well as committed intellectuals from different disciplines. Against this diversified background Marxism had to prove its mettle, a requirement that explains the unique internal differentiation and pluralism within Polish Marxist philosophy. The decisive factors in its development were its rejection of Soviet Marxism-Leninism and the opening to Western Marxism. The often remarked ‘revisionist’ character of Polish Marxism consists in the recognition by its most talented representatives of the fundamental incompatibility between Marxism as the ideological legitimation of the Communist state and as a philosophy subject to rational criteria. In effect, Polish Marxists thought the theory through to its end, and in this sense brought to light its inherently unstable nature: to be a philosophy it would have to cease to be Marxist, to be Marxist means having to pander to ideology. The confrontation of the diverse currents in Polish philosophy contributed to an unfortunate result: for political reasons non-Marxists steered clear of social philosophical questions, while official Marxism, which suppressed the ‘revisionist’ trend, obfuscated the relation between philosophy and social reality. Today philosophy in Poland has the urgent task to contribute to the reconstruction of a social rationality combining a critical consciousness with moral elements of commitment and responsibility.

Notes: Abstract We present the results of an 8.4 GHz VLA survey of the CfA Seyferts. We find that the luminosity functions for Seyfert 1s and 2s are essentially identical, but that the type 2 objects are more likely to contain extended radio structures. This seems to be consistent with unified models for Seyferts, in which the differences between the two classes are largely due to orientation effects.

Notes: The mechanistic and synthetic aspects of the addition reaction of thioxophosphorane sulfenyl bromide with ethyl vinyl ether were studied in detail by NMR techniques. It has been found that the regiospecific, primary product of the reaction, 1-bromo-1-ethoxy-2S(dialkoxythiophosphoryl)ethane I, is unstable and undergoes slow decomposition to give four compounds. The formation of thiophosphoryl derivatives, vinyl ethers II and III, aldehyde IV, and the symmetrical hemiacetal anhydride V, has been considered in terms of a carbocation intermediate. By choice of the appropriate reaction conditions, the aldehyde IV can be obtained in very high yield.

Notes: The crystal and molecular structures of the title compounds were determined by X-ray diffraction technique from diffractometer intensity measurements. It has been found that two homologous disulfides, bis(dimethoxythiophosphoryl) disulfide 1 and bis(dineopentoxythiophosphoryl) disulfide 2, form different molecular and crystal structures with space groups C2/c and P&1macr;, respectively. These results were confirmed by 31P CP MAS NMR studies, which showed that under favorable conditions the solid state NMR may lead to determination of the number of crystallographically unique phosphorus atoms. Moreover, the variation of the disulfide S-S bond length versus torsional P-S-S-P angles was observed.