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  • Yayın
    An essential approach to the architecture of diatomic molecules: 2. how are size, vibrational period of time, and mass interrelated?
    (Optical Soc Amer, 2004-11) Yarman, Nuh Tolga
    In our previous article, we arrived at an essential relationship for T the classical vibrational period of a given diatomic molecule, at the total electronic energy E-, i.e., T = [4pi(2)/(rootn(1)n(2)h)] rootgM(0)m(e) R-2, where M-0 to is the reduced mass of the nuclei; m(3) is the mass of the electron; R is the internuclear distance: g is a dimensionless and relativistically invariant coefficient, roughly around unity; and n(1) and n(2) are the principal quantum numbers of electrons making up the bond(s) of the diatomic molecule, which, because of quantum defects. are not integer numbers. The above relationship holds generally. It essentially yields T similar to R 2 for the classical vibrational period versus the square of the internuclear distance in different electronic states of a given molecule. which happens to be an approximate relationship known since 1925 but not understood until now. For similarly configured electronic states, we determine n(1)n(2) to be R/R-0, where R is the internuclear distance in the given electronic state and R-0 is the internuclear distance in the ground state. Furthermore. from the analysis of H-2 spectroscopic data, we found out that the ambiguous states of this molecule are configured like alkali hydrides and Li-2. This suggests that, quantum mechanically, on the basis of an equivalent H-2 excited state. we can describe well, for example, the ground state of Li-2. On the basis of this interesting finding, herein we propose to associate the quantum numbers n(1) and n2 With the bond electrons of the ground state of any diatomic molecule belonging to a given chemical family in reference to the ground state of a diatomic molecule still belonging to this family but bearing, say, the lowest classical vibrational period, since g, depending only on the electronic configuration. will stay nearly constant throughout. This allows us to draw up a complete systematization of diatomic molecules given that g (appearing to be dependent purely on the electronic structure of the molecule) stays constant for chemically alike molecules and n(1)n(2) can be identified to be R-0/R-00 for diatomic molecules whose bonds are electronically configured in the same way, R-00 then being the internuclear distance of the ground state of the molecule chosen as the reference molecule within the chemical fan-Lily under consideration. Our approach discloses the simple architecture of diatomic molecules, otherwise hidden behind a much too cumbersome quantum-mechanical description. This architecture, telling how the vibrational period of Lime. size. and mass are determined, is Lorentz-invariant and can be considered as the mechanism of the behavior of the quantities in question in interrelation with each other when the molecule is brought into uniform translational motion or transplanted into a gravitational field or, in fact, any field with which it can interact.
  • Yayın
    Bifurcation of drift shells near the dayside magnetopause
    (Amer Geophysical Union, 2007-07-10) Öztürk, Mehmet Kaan; Wolf, Richard A.
    Close to the dayside magnetopause, there is a region of space where each field line has two magnetic field minima, one near each cusp. That region is located around local noon, and extends about 1-2 R-e from the magnetopause. Particles that enter this region with equatorial pitch angles sufficiently close to 90 degrees will cross the dayside not along an equatorial path, but along one of the two branches on either side of the equatorial plane. The two branches are joined again past local noon. This process of drift-shell bifurcation (DSB) is nonadiabatic even under static conditions. Two physical mechanisms can cause this nonadiabaticity: one that is operative for nearly all magnetospheric magnetic field configurations and another that depends on a particular combination of north-south and east-west asymmetry in the magnetic field. This paper deals only with the first mechanism. For configurations with north-south and east-west symmetry, DSB changes the second invariant I of the motion by a small amount that is of the order of the gyroradius (the first invariant is intact). For near-equatorial particles (I approximate to 0) the change can be significantly larger. Assuming north-south and dawn-dusk symmetry, we present general theoretical expressions for the second-invariant jump Delta I, which can be applied to a variety of magnetic field models. The results show that Delta I is sensitively dependent on the bounce phase of the particle at the bifurcation line. The RMS value of Delta I over a bounce-phase ensemble increases with decreasing mirror field and with increasing kinetic energy. We verify these results with test-particle simulations using model magnetic fields.