scholarly journals Block-diagonalization problem for the common Hückel-type Hamiltonian matrix of alternant hydrocarbons and its nonperturbative solution

2004 ◽  
Vol 101 (3) ◽  
pp. 274-282 ◽  
Author(s):  
V. Gineityte
Keyword(s):  
Hamiltonian Matrix ◽  
Block Diagonalization ◽  
Nonperturbative Solution ◽  
The Common ◽  
Alternant Hydrocarbons

Facilitating Kinetic Stability Estimates for Classical 2m Alternant Hydrocarbons

2008 ◽  
Vol 61 (1) ◽  
pp. 36 ◽  
Author(s):  
Richard F. Langler
Keyword(s):  
Kinetic Stability ◽  
Stability Estimates ◽  
New Techniques ◽  
Common Bond ◽  
Structural Modifications ◽  
Partial Coefficient ◽  
Alternant Hydrocarbon ◽  
The Common ◽  
Alternant Hydrocarbons ◽  
Formal Relationship

New techniques, coefficient embedding, and partial coefficient embedding are developed. Dense Sachs’ subgraphs are introduced to facilitate partial coefficient embedding. The symbol p is introduced to denote the formal relationship between a pair of fused elementary circuits and the larger circuit obtained by deleting the common bond between them. These techniques simplify and accelerate the evaluation of proposed structural modifications as they relate to altering kinetic stability for any even, classical, alternant hydrocarbon π system.

scholarly journals Diabatic potential energy curves for the $$^4{\Pi} $$ states of SH

2021 ◽  
Vol 140 (6) ◽  
Author(s):  
D. O. Kashinski ◽  
J. Bohnemann ◽  
A. P. Hickman ◽  
D. Talbi
Keyword(s):  
Potential Energy ◽  
High Accuracy ◽  
Potential Energy Curves ◽  
Hamiltonian Matrix ◽  
Block Diagonalization ◽  
Diagonalization Method ◽  
Avoided Crossings ◽  
Diabatic Representation ◽  
Nuclear Geometry ◽  
Valence Mixing

AbstractWe present a diabatic representation of the potential energy curves (PECs) for the $$^4{{\Pi}} $$ 4 Π states of $$\mathrm {SH}$$ SH . Multireference, configuration interaction (MRCI) calculations were used to determine high-accuracy adiabatic PECs of both $$\mathrm {SH}$$ SH and $${\mathrm {SH}}^+$$ SH + from which the diabatic representation is constructed for $$\mathrm {SH}$$ SH . The adiabatic PECs exhibit many avoided crossings due to strong Rydberg-valence mixing. We employ the block diagonalization method, an orthonormal rotation of the adiabatic Hamiltonian, to disentangle the valence autoionizing and Rydberg $$^4\Pi $$ 4 Π states of $$\mathrm {SH}$$ SH by constructing a diabatic Hamiltonian. The diagonal elements of the diabatic Hamiltonian matrix at each nuclear geometry render the diabatic PECs and the off-diagonal elements are related to the state-to-state coupling. Care is taken to assure smooth variation and consistency of chemically significant molecular orbitals across the entire geometry domain.

Catalogue reduction techniques

1978 ◽  
Vol 48 ◽  
pp. 389-390 ◽  
Author(s):  
Chr. de Vegt
Keyword(s):  
Adjustment Process ◽  
Proper Motions ◽  
Measuring Process ◽  
Aerial Photogrammetry ◽  
Reduction Techniques ◽  
Observational Technique ◽  
The Common ◽  
Astrometric Data

AbstractReduction techniques as applied to astrometric data material tend to split up traditionally into at least two different classes according to the observational technique used, namely transit circle observations and photographic observations. Although it is not realized fully in practice at present, the application of a blockadjustment technique for all kind of catalogue reductions is suggested. The term blockadjustment shall denote in this context the common adjustment of the principal unknowns which are the positions, proper motions and certain reduction parameters modelling the systematic properties of the observational process. Especially for old epoch catalogue data we frequently meet the situation that no independent detailed information on the telescope properties and other instrumental parameters, describing for example the measuring process, is available from special calibration observations or measurements; therefore the adjustment process should be highly self-calibrating, that means: all necessary information has to be extracted from the catalogue data themselves. Successful applications of this concept have been made already in the field of aerial photogrammetry.

Renilla Bioluminescence: A Morphologic Approach to the Location of Photocytes

1974 ◽  
Vol 32 ◽  
pp. 208-209
Author(s):  
Ben O. Spurlock ◽  
Milton J. Cormier
Keyword(s):  
Excited State ◽  
Ground State ◽  
Molecular Basis ◽  
Light Emission ◽  
Chemical Basis ◽  
Electronic Excited State ◽  
Colonial Form ◽  
The Common ◽  
Eighteenth And Nineteenth Centuries ◽  
Catalyzed Oxidation

The phenomenon of bioluminescence has fascinated layman and scientist alike for many centuries. During the eighteenth and nineteenth centuries a number of observations were reported on the physiology of bioluminescence in Renilla, the common sea pansy. More recently biochemists have directed their attention to the molecular basis of luminosity in this colonial form. These studies have centered primarily on defining the chemical basis for bioluminescence and its control. It is now established that bioluminescence in Renilla arises due to the luciferase-catalyzed oxidation of luciferin. This results in the creation of a product (oxyluciferin) in an electronic excited state. The transition of oxyluciferin from its excited state to the ground state leads to light emission.

Mammalian Bone Marrow Acetylcholinesterase

1982 ◽  
Vol 40 ◽  
pp. 44-45
Author(s):  
Ezzatollah Keyhani
Keyword(s):  
Central Nervous System ◽  
Bone Marrow ◽  
Nervous System ◽  
Common Property ◽  
Extracellular Medium ◽  
The Central Nervous System ◽  
The Common ◽  
Mammalian Bone

Acetylcholinesterase (EC 3.1.1.7) (ACHE) has been localized at cholinergic junctions both in the central nervous system and at the periphery and it functions in neurotransmission. ACHE was also found in other tissues without involvement in neurotransmission, but exhibiting the common property of transporting water and ions. This communication describes intracellular ACHE in mammalian bone marrow and its secretion into the extracellular medium.

Sign in / Sign up

Export Citation Format

Share Document