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College of Sciences and Mathematics: Recent submissions

Now showing items 201-220 of 393

Indirect Impacts of Recreational Scuba Diving: Patterns of Growth and Predation in Branching Stony Corals 

Guzner, Barak; Novplansky, Ariel; Shalit, Or; Chadwick, Nanette E. (2021-01-27)
The highest recorded rates of recreational SCUBA diving occur on coral reefs at Eilat in the northern Red Sea, where many scleractinian corals are damaged by physical contact with divers. We compared coral skeletal growth ...

Anatomy of the Laminar Organs of Commelina erecta (Commelinaceae) 

Dute, Roland R.; Jackson, Brian E.; Adkins, Ryan D.; Folkerts, Debbie R. (2021-01-27)
A study was undertaken to compare the anatomy of the laminar floral parts with that of the spathes and leaves of Commelina erecta L. Each flower has two types of petals and two types of sepals. In contrast to the other ...

Electron binding energies and Dyson orbitals of Al(5)O(m)(-) (m=3,4,5) and Al(5)O(5)H(2)(-) 

Guevara-Garcia, Alfredo; Martinez, Ana; Ortiz, J.V. (2021-01-26)
Photoelectron spectra of Al5Om − m=3–5 and of the anion produced by the dissociative adsorption of a water molecule by Al5O4 − are interpreted with density-functional geometry optimizations and electron-propagator ...

Assessment of transition operator reference states in electron propagator calculations 

Flores-Moreno, Roberto; Zakrzewski, V. G.; Ortiz, J.V. (2021-01-26)
The transition operator method combined with second-order, self-energy corrections to the electron propagator TOEP2 may be used to calculate valence and core-electron binding energies. This method is tested on a set of ...

OH3- and O2H5- double Rydberg anions: Predictions and comparisons with NH4- and N2H7- 

Melin, Junia; Ortiz, J.V. (2021-01-26)
A low barrier in the reaction pathway between the double Rydberg isomer of OH3 − and a hydride-water complex indicates that the former species is more difficult to isolate and characterize through anion photoelectron ...

Surface Green’s function calculations: A nonrecursive scheme with an infinite number of principal layers 

Kletsov, Aleksey; Dahnovsky, Yuri; Ortiz, J.V. (2021-01-26)
A novel computational method for a surface Green’s function matrix is introduced for the calculation of electrical current in molecular wires. The proposed nonrecursive approach includes an infinite number of principal ...

Sequential addition of H2O, CH3OH, and NH3 to Al3O3-: A theoretical study 

Guevara-Garcia, Alfredo; Martinez, Ana; Ortiz, J.V. (2021-01-26)
Photoelectron spectra of two species, Al3O3(H2O)(2)(-) and Al3O3(CH3OH)(2)(-), that are produced by the addition of two water or methanol molecules to Al3O3- are interpreted with density-functional geometry optimizations ...

Integral approximations in ab initio, electron propagator calculations 

Flores-Moreno, Roberto; Ortiz, J.V. (2021-01-26)
Treatments of interelectronic repulsion that avoid four-center integrals have been incorporated in ab initio, electron-propagator calculations with diagonal self-energy matrices. Whereas the formal scaling of arithmetic ...

Partial photoionization cross sections of and Rydberg radicals 

Velasco, A.M.; Lavin, C.; Martin, I.; Melin, J.; Ortiz, J.V. (2021-01-26)
ammonium and oxonium Rydberg radicals from the outermost, occupied orbitals of their respective ground states are reported. These properties are known to be relevant in photoelectron dynamics studies. For the present ...

Delocalized water and fluoride contributions to Dyson orbitals for electron detachment from the hydrated fluoride anion 

Canuto, Sylvio; Coutinho, Kaline; Cabral, Benedito J. C.; Zakrzewski, V. G.; Ortiz, J.V. (2021-01-26)
The experimental vertical electron detachment energy VEDE of aqueous fluoride, F− H2O , is approximately 9.8 eV, but spectral assignment is complicated by interference between F− 2p and H2O 1b1 orbitals. The electronic ...

Quasiparticle virtual orbitals in electron propagator calculations 

Flores-Moreno, Roberto; Ortiz, J.V. (2021-01-26)
The computational limits of accurate electron propagator methods for the calculation of electron binding energies of large molecules are usually determined by the rank of the virtual orbital space. Electron density ...

Second-order, two-electron Dyson propagator theory: Comparisons for vertical double ionization potentials 

Ida, T.; Ortiz, J.V. (2021-01-26)
The second-order, two-electron Dyson propagator is derived using superoperator theory with a spin-adapted formulation. To include certain ladder diagrams to all orders, the shifted-denominator SD2 approximation is made. ...

Electron propagator calculations on C-60 and C-70 photoelectron spectra 

Zakrzewski, V. G.; Dolgounitcheva, O.; Ortiz, J.V. (2021-01-26)
Vertical ionization energies of C60 and C70 fullerenes are calculated with semidirect implementations of electron propagator methods and a triple- plus polarization basis set. These predictions are in close agreement ...

Efficient evaluation of analytic Fukui functions 

Flores-Moreno, Roberto; Melin, Junia; Ortiz, J.V.; Merino, Gabriel (2021-01-26)
An efficient method for the analytic evaluation of Fukui functions is proposed. Working equations are derived and numerical results are used to validate the method on medium size set of molecules. In addition to the ...

Electron propagator and coupled-cluster calculations on the photoelectron spectra of thiouracil and dithiouracil anions 

Dolgounitcheava, O.; Zakrzewski, V. G.; Ortiz, J. V. (2021-01-26)
Electron affinities, vertical electron detachment energies, and isomerization energies of 4-thiouracil, 2-thiouracil, and 2,4-dithiouracil and their valence anions have been calculated with ab initio electron propagator ...

Biology of Ultramafic Rocks and Soils: Research Goals for the Future 

Boyd, Robert S.; Kruckeberg, Arthur R.; Rajakaruna, Nishanta (2021-01-04)

Do Tropical Nickel Hyperaccumulators Mobilize Metals into Epiphytes? A Test Using Bryophytes from New Caledonia 

Boyd, Robert S.; Wall, Michael A.; Jaffré, Tanguy (2021-01-04)
Hyperaccumulator plants mobilize large amounts of certain elements from the soil into their tissues. Those elements then may be transferred to other organisms in those communities. Using a humid tropical forest site in ...

Variation of Morphology and Elemental Concentrations in the California Nickel Hyperaccumulator Streptanthus polygaloides (Brassicaceae) 

Boyd, Robert S.; Wall, Michael A.; Santos, Scott R.; Davis, Michael A. (2021-01-04)
The Ni hyperaccumulator Strepthanthus polygaloides (Brassicaceae) is one of a handful of Ni hyperaccumulators known from continental North America. Surveys have revealed four distinctive morphs of this species, relying ...

Elemental Concentrations of Eleven New Caledonian Plant Species from Serpentine Soils: Elemental Correlations and Leaf-Age Effects 

Boyd, Robert S.; Jaffré, Tanguy (2021-01-04)
- We investigated accumulation of elements (Ca, Co, Cr, Cu, Fe, K, Mg, Mn, P, Pb, and Zn) in leaves of different ages for 11 evergreen woody plant species from serpentine soils of New Caledonia. Species were classifi ed ...