4,182 research outputs found

    Generating Converging Bounds to the (Complex) Discrete States of the P2+iX3+iαXP^2 + iX^3 + i\alpha X Hamiltonian

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    The Eigenvalue Moment Method (EMM), Handy (2001), Handy and Wang (2001)) is applied to the HαP2+iX3+iαXH_\alpha \equiv P^2 + iX^3 + i\alpha X Hamiltonian, enabling the algebraic/numerical generation of converging bounds to the complex energies of the L2L^2 states, as argued (through asymptotic methods) by Delabaere and Trinh (J. Phys. A: Math. Gen. {\bf 33} 8771 (2000)).Comment: Submitted to J. Phys.

    Extension of a Spectral Bounding Method to Complex Rotated Hamiltonians, with Application to p2ix3p^2-ix^3

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    We show that a recently developed method for generating bounds for the discrete energy states of the non-hermitian ix3-ix^3 potential (Handy 2001) is applicable to complex rotated versions of the Hamiltonian. This has important implications for extension of the method in the analysis of resonant states, Regge poles, and general bound states in the complex plane (Bender and Boettcher (1998)).Comment: Submitted to J. Phys.

    Generating Bounds for the Ground State Energy of the Infinite Quantum Lens Potential

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    Moment based methods have produced efficient multiscale quantization algorithms for solving singular perturbation/strong coupling problems. One of these, the Eigenvalue Moment Method (EMM), developed by Handy et al (Phys. Rev. Lett.{\bf 55}, 931 (1985); ibid, {\bf 60}, 253 (1988b)), generates converging lower and upper bounds to a specific discrete state energy, once the signature property of the associated wavefunction is known. This method is particularly effective for multidimensional, bosonic ground state problems, since the corresponding wavefunction must be of uniform signature, and can be taken to be positive. Despite this, the vast majority of problems studied have been on unbounded domains. The important problem of an electron in an infinite quantum lens potential defines a challenging extension of EMM to systems defined on a compact domain. We investigate this here, and introduce novel modifications to the conventional EMM formalism that facilitate its adaptability to the required boundary conditions.Comment: Submitted to J. Phys.

    Perancangan Interior Japanese Action Figure Center Di Surabaya

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    Japanese Action Figure Center in Surabaya is intended for lovers of action figures to be able to buy , assemble , and respond to their needs to provide a place that has the style of anime in Surabaya . The concept of this design is stylish and modern techno , which impressed futuristic design , and followed by the use of advanced technology in order to access the facilities in place . Brand image of the product sold itself is "imaginative and communicative " where the figure lovers will immediately be able to imagine the feel of the place is so into it . Therefore the design of the room is really an implementation of anime , or the character of the game , combined with a modern interior style

    Benchmark full configuration-interaction calculations on HF and NH2

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    Full configuration-interaction (FCI) calculations are performed at selected geometries for the 1-sigma(+) state of HF and the 2-B(1) and 2-A(1) states of NH2 using both DZ and DZP gaussian basis sets. Higher excitations become more important when the bonds are stretched and the self-consistent field (SCF) reference becomes a poorer zeroth-order description of the wave function. The complete active space SCF - multireference configuration-interaction (CASSCF-MRCI) procedure gives excellent agreement with the FCI potentials, especially when corrected with a multi-reference analog of the Davidson correction

    Eigenvalues of PT-symmetric oscillators with polynomial potentials

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    We study the eigenvalue problem u(z)[(iz)m+Pm1(iz)]u(z)=λu(z)-u^{\prime\prime}(z)-[(iz)^m+P_{m-1}(iz)]u(z)=\lambda u(z) with the boundary conditions that u(z)u(z) decays to zero as zz tends to infinity along the rays argz=π2±2πm+2\arg z=-\frac{\pi}{2}\pm \frac{2\pi}{m+2}, where Pm1(z)=a1zm1+a2zm2+...+am1zP_{m-1}(z)=a_1 z^{m-1}+a_2 z^{m-2}+...+a_{m-1} z is a polynomial and integers m3m\geq 3. We provide an asymptotic expansion of the eigenvalues λn\lambda_n as n+n\to+\infty, and prove that for each {\it real} polynomial Pm1P_{m-1}, the eigenvalues are all real and positive, with only finitely many exceptions.Comment: 23 pages, 1 figure. v2: equation (14) as well as a few subsequent equations has been changed. v3: typos correcte

    Kinetic-energy systems, density scaling, and homogeneity relations in density-functional theory

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    We examine the behavior of the Kohn-Sham kinetic energy T_s[ρ] and the interacting kinetic energy T[ρ] under homogeneous density scaling, ρ(r)→ζρ(r). Using convexity arguments, we derive simple inequalities and scaling constraints for the kinetic energy. We also demonstrate that a recently derived homogeneity relation for the kinetic energy [S. B. Liu and R. G. Parr, Chem. Phys. Lett. 278, 341 (1997)] does not hold in real systems, due to nonsmoothness of the kinetic-energy functional. We carry out a numerical study of the density scaling of T_s[ρ] using ab initio densities, and find it exhibits an effective homogeneity close to 5/3. We also explore alternative reference systems for the kinetic energy which have fewer particles than the true N-particle interacting system. However, we conclude that the Kohn-Sham reference system is the only viable choice for accurate calculation, as it contains the necessary physics

    A new chemical concept: Shape chemical potentials

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    Within the density functional formalism, we introduce the shape chemical potential μ_i(^n) for subsystems, which in the limiting case of point subsystems, is a local chemical potential μ^n(r). It describes the electron withdrawing/donating ability of specified density fragments. The shape chemical potential does not equalize between subsystems, and provides a powerful new method to identify and describe local features of molecular systems. We explore the formal properties of μ_i(^n) especially with respect to discontinuities, and reconcile our results with Sanderson’s principle. We also perform preliminary calculations on model systems of atoms in molecules, and atomic shell structure, demonstrating how μ_i(^n) and μ^n(r), identify and characterize chemical features as regions of different shape chemical potential. We present arguments that shell structure, and other chemical features, are not ever obtainable within Thomas–Fermi-type theories
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