ALBERT

All Library Books, journals and Electronic Records Telegrafenberg

X
feed icon rss

Your email was sent successfully. Check your inbox.

An error occurred while sending the email. Please try again.

Proceed reservation?

Export
  • 1
    Electronic Resource
    Electronic Resource
    Observation of the XY- abstraction products in the ion-molecule reactions X- + RY .fwdarw. XY- + R: an alternative to the SN2 mechanism at suprathermal collision energies (1995)
    s.l. : American Chemical Society
    Journal of the American Chemical Society 117 (1995), S. 1828-1832 
    Details
    ISSN: 1520-5126
    Source: ACS Legacy Archives
    Topics: Chemistry and Pharmacology
    Type of Medium: Electronic Resource
    URL: http://dx.doi.org/10.1021/ja00111a023
    Location Call Number Expected Availability
    BibTip Others were also interested in ...
    Paper (German National Licenses)
    Fulltext
  • 2
    Electronic Resource
    Electronic Resource
    Molecular Simulation of Permeation of Small Penetrants through Membranes. 1. Diffusion Coefficients (1994)
    s.l. : American Chemical Society
    Macromolecules 27 (1994), S. 4498-4508 
    Details
    ISSN: 1520-5835
    Source: ACS Legacy Archives
    Topics: Chemistry and Pharmacology , Physics
    Type of Medium: Electronic Resource
    URL: http://dx.doi.org/10.1021/ma00094a011
    Location Call Number Expected Availability
    BibTip Others were also interested in ...
    Paper (German National Licenses)
    Fulltext
  • 3
    Electronic Resource
    Electronic Resource
    Molecular Simulation of Permeation of Small Penetrants through Membranes. 2. Solubilities (1995)
    s.l. : American Chemical Society
    Macromolecules 28 (1995), S. 2544-2554 
    Details
    ISSN: 1520-5835
    Source: ACS Legacy Archives
    Topics: Chemistry and Pharmacology , Physics
    Type of Medium: Electronic Resource
    URL: http://dx.doi.org/10.1021/ma00111a058
    Location Call Number Expected Availability
    BibTip Others were also interested in ...
    Paper (German National Licenses)
    Fulltext
  • 4
    Electronic Resource
    Electronic Resource
    Fluctuation, relaxations, and hydration in liquid water. Hydrogen-bond rearrangement dynamics (1993)
    s.l. : American Chemical Society
    Chemical reviews 93 (1993), S. 2545-2566 
    Details
    ISSN: 1520-6890
    Source: ACS Legacy Archives
    Topics: Chemistry and Pharmacology
    Type of Medium: Electronic Resource
    URL: http://dx.doi.org/10.1021/cr00023a011
    Location Call Number Expected Availability
    BibTip Others were also interested in ...
    Paper (German National Licenses)
    Fulltext
  • 5
    Electronic Resource
    Electronic Resource
    Hydrophobic hydration of inert gases: Thermodynamic properties, inherent structures, and normal-mode analysis (1991)
    College Park, Md. : American Institute of Physics (AIP)
    The Journal of Chemical Physics 95 (1991), S. 3719-3727 
    Details
    ISSN: 1089-7690
    Source: AIP Digital Archive
    Topics: Physics , Chemistry and Pharmacology
    Notes: Computer simulations on water and aqueous solutions of noble gases have been carried out in order to study the structures of water around a solute. The hydration energy and free energy evaluated for neon (Ne) and xenon (Xe) solutions in the present study were in good agreement with those by experiments. The detailed hydration structures were investigated by means of the so called inherent structures and normal-mode analyses. It was found that the positive excess free energy in the hydration of Xe arises from a decrease in the number of distinct potential-energy minima in configuration space and that the free energy increase in the Ne solution is due partly to the decrease in the number of the potential minima and partly to the anharmonic modes which are harder than those in pure water. The soft anharmonic modes in the Xe solution were almost equivalent to those in pure water. The introduction of a Xe solute gives rise to a change in water structure to a clathrate-like structure and yields an increase in population of the cyclic pentamer connected by hydrogen bonds, which leads to the exothermic hydration.
    Type of Medium: Electronic Resource
    URL: http://dx.doi.org/10.1063/1.460822
    Location Call Number Expected Availability
    BibTip Others were also interested in ...
    Paper (German National Licenses)
    Fulltext
  • 6
    Electronic Resource
    Electronic Resource
    Large local energy fluctuations in water. II. Cooperative motions and fluctuations (1988)
    College Park, Md. : American Institute of Physics (AIP)
    The Journal of Chemical Physics 89 (1988), S. 5852-5860 
    Details
    ISSN: 1089-7690
    Source: AIP Digital Archive
    Topics: Physics , Chemistry and Pharmacology
    Notes: Large local energy fluctuations in liquid water and their physical origin are investigated by using classical molecular dynamics (MD) calculation and quenching techniques. Performing a trajectory calculation of 100 ps, it is found that large rotational motions of individual water molecules, which are always associated with potential energy destabilization of 10–20 kcal/mol, occur once in about 10 ps. The stabilization and destabilization of the individual water molecules are induced by cooperative motions. In order to analyze these cooperative motions in the liquid water, the water structures are quenched to their local minima (called the inherent structures). Comparing the inherent structures successively visited by the system, it is found that collective motions of about 10–40 molecules localized in space occur in unstable regions. The potential energy fluctuation of an individual molecule can reach up to 15 kcal/mol even in the inherent structures. The strong potential energy correlation among neighboring molecules indicates these cooperative motions cause the "flip–flop''-type energy exchanges; as a molecule is stabilized, another is to be unstabilized and vice versa. A flip-flop motion does not involve a (large) energy barrier but causes large energy fluctuations of the individual molecules. A large portion of potential energy fluctuations of the individual water molecules is accounted for as the superposition of fluctuations in the inherent structures and those in the normal modes build upon these structures.
    Type of Medium: Electronic Resource
    URL: http://dx.doi.org/10.1063/1.455536
    Location Call Number Expected Availability
    BibTip Others were also interested in ...
    Paper (German National Licenses)
    Fulltext
  • 7
    Electronic Resource
    Electronic Resource
    Integral equation and Monte Carlo study on hydrophobic effects: Size dependence of apolar solutes on solute–solute interactions and structures of water (1987)
    College Park, Md. : American Institute of Physics (AIP)
    The Journal of Chemical Physics 86 (1987), S. 1512-1520 
    Details
    ISSN: 1089-7690
    Source: AIP Digital Archive
    Topics: Physics , Chemistry and Pharmacology
    Notes: Hydrophobic effects for various solute sizes have been investigated by the RISM equation and Monte Carlo simulation. It is shown that the association of solute molecules is enhanced by the hydrogen bonds among water molecules. The degree of association depends on the solute size. For a large apolar solute, the structure of water is enhanced, resulting in the exothermic hydration and the negative entropy change in hydration. For a solute comparable with the water size, the hydrogen bonds among water molecules are strengthened but the net hydrogen bonds number does not increase. These results are also confirmed by the analysis of the geometric patterns formed by the hydrogen bond network. It is shown that the ordered structure of water in the solution of the large solutes gives rise to the larger enthalpy of the hydration, and thus they are more soluble in water than the smaller solutes.
    Type of Medium: Electronic Resource
    URL: http://dx.doi.org/10.1063/1.452188
    Location Call Number Expected Availability
    BibTip Others were also interested in ...
    Paper (German National Licenses)
    Fulltext
  • 8
    Electronic Resource
    Electronic Resource
    Potential energy surfaces for water dynamics. II. Vibrational mode excitations, mixing, and relaxations (1990)
    College Park, Md. : American Institute of Physics (AIP)
    The Journal of Chemical Physics 93 (1990), S. 8138-8147 
    Details
    ISSN: 1089-7690
    Source: AIP Digital Archive
    Topics: Physics , Chemistry and Pharmacology
    Notes: Dynamical behavior of liquid water is investigated by analyzing the potential energy surface involved. Multidimensional properties of the potential energy surface are explored in terms of vibrational mode excitations at its local energy minima, called inherent structures. The vibrational mode dynamics, especially mechanism of mode relaxation and structure transitions, is analyzed. It shows very strong excitation energy dependence and mode dependence. There are three kinds of vibrational coupling among modes. For excitations of energy near the room temperature, most modes (more than 90% of total modes) individually interact with only one or two other modes, and yield near recurrence of the mode energy in a few tens picoseconds (very slow relaxation). Spatially localized modes in the intermediate frequency range couple with many delocalized modes, yielding fast relaxation. The coupling is governed by atomic displacement overlaps and frequency matching. Each mode couples with nearby frequency or double frequency modes through the Fermi resonance. Lowest frequency modes almost always lead to transitions from a potential energy well to neighbor potential wells, called inherent structure transitions. In high energy excitation, some intermediate frequency modes also yield such transitions. There exist very low energy paths involving single or few water molecule displacements at almost every inherent structure, indicating that certain facile molecular movements occur even in very low temperature states. Different energy excitations of a low frequency mode result in different inherent structure transitions; transitions caused by high energy excitations involve many large molecular displacements. These inherent structure transitions are the source of the water binding structural reorganization dynamics. Significance of these vibrational mode dynamics in the water dynamics is discussed.
    Type of Medium: Electronic Resource
    URL: http://dx.doi.org/10.1063/1.459344
    Location Call Number Expected Availability
    BibTip Others were also interested in ...
    Paper (German National Licenses)
    Fulltext
  • 9
    Electronic Resource
    Electronic Resource
    Large local energy fluctuations in water (1987)
    College Park, Md. : American Institute of Physics (AIP)
    The Journal of Chemical Physics 87 (1987), S. 6128-6139 
    Details
    ISSN: 1089-7690
    Source: AIP Digital Archive
    Topics: Physics , Chemistry and Pharmacology
    Notes: A detailed analysis is made for the dynamical behavior of an individual water molecule in liquid water by using a classical molecular dynamics (MD) calculation. It is found that there exist very large potential energy fluctuations in water; a single water molecule can exhibit a fluctuation of the order of 10∼20 kcal/mol. These potential energy fluctuations can be classified into two categories; the fast component (10−14–10−13 s) associated with librational motions of water molecules and the slow component (10−12–10−11 s) associated with water binding structure changes. Both amplitudes can be reached up to 10 kcal/mol. Due to strong Coulomb (dipole–dipole) interaction, small mutual geometrical changes, caused by the libration motions, induce large fast potential energy fluctuations. Due to large cohesion energy of the hydrogen bond and the nature of the water binding structure, there exist many water pair interactions which are unattactive or even repulsive; the water molecule potential (binding) energy distribution is inhomogeneous in space. This inhomogeneity alters as the water structure changes. Each water molecule then makes a transition from a stable binding to an unstable one with surrounding molecules and vice versa, inducing large potential energy changes in the picosecond order. A detailed analysis is made concerning how the hydrogen bonding pattern changes with water molecular motions. Significance of the existence of large water potential energy fluctuations on chemical processes is discussed.
    Type of Medium: Electronic Resource
    URL: http://dx.doi.org/10.1063/1.453487
    Location Call Number Expected Availability
    BibTip Others were also interested in ...
    Paper (German National Licenses)
    Fulltext
  • 10
    Electronic Resource
    Electronic Resource
    Potential energy surfaces for water dynamics: Reaction coordinates, transition states, and normal mode analyses (1989)
    College Park, Md. : American Institute of Physics (AIP)
    The Journal of Chemical Physics 91 (1989), S. 6318-6327 
    Details
    ISSN: 1089-7690
    Source: AIP Digital Archive
    Topics: Physics , Chemistry and Pharmacology
    Notes: Dynamics of water binding structure reorganization is investigated by analyzing the potential energy surfaces involved. The water structures in a trajectory are quenched to their local minima, called the inherent structures. The reaction coordinates, which connect the inherent structures successively visited by the system, are determined. It is found that the energy barrier heights, the transition state energies, along the reaction coordinates are mostly distributed in the range of 0.2–6 kcal/mol. The classification of inherent structures is made to groups of "overall-inherent structures''; successive inherent structures are most often not so geometrically distinct. It is found that transitions between the overall-inherent structures, involving large collective motions, occur in the subpicosecond time scale. Individual molecular motions in these collective motions are stongly correlated, not yielding large transition energies. The transition state energy sometimes reaches up to 20 kcal/mol, when the system goes through the ridge between deep minima, yielding ballistic dynamical behavior. Temperature dependence of the collective motions is also investigated.
    Type of Medium: Electronic Resource
    URL: http://dx.doi.org/10.1063/1.457399
    Location Call Number Expected Availability
    BibTip Others were also interested in ...
    Paper (German National Licenses)
    Fulltext
Close ⊗
This website uses cookies and the analysis tool Matomo. More information can be found here...