By the use of complete orthonormal sets of psi(alpha)-ETOs (alpha=1, 0, m1, m2,...) introduced by the author, new addition theorems are derived for STOs and arbitrary central and noncentral interaction potentials (CIPs and NCIPs). The expansion coefficients in these addition theorems are expressed through the Gaunt and Gegenbauer coefficients. Using the addition theorems obtained for STOs and potentials, general formulae in terms of three-center overlap integrals are established for the multicenter t-electron integrals of CIPs and NCIPs that arise in the solution of the N-electron atomic and molecular problem (2hthN) when a Hylleraas approximation in Hartree-Fock-Roothaan theory is employed. With the help of expansion formulae for translation of STOs, the three-center overlap integrals are expressed through the two-center overlap integrals. The formulae obtained are valid for arbitrary quantum numbers, screening constants and location of orbitals.
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http://dx.doi.org/10.1007/s00894-003-0134-0 | DOI Listing |
J Phys Chem A
January 2025
Hylleraas Centre, Department of Chemistry, UiT the Arctic University of Norway, Tromso̷ N-9037, Norway.
We introduce a method for computing quantum mechanical forces through surface integrals over the stress tensor within the framework of the density functional theory. This approach avoids the inaccuracies of traditional force calculations using the Hellmann-Feynman theorem when applied to multiresolution wavelet representations of orbitals. By integrating the quantum mechanical stress tensor over surfaces that enclose individual nuclei, we achieve highly accurate forces that exhibit superior consistency with the potential energy surface.
View Article and Find Full Text PDFSci Data
January 2025
Division of Biomechanics and Research Development, Department of Biomechanics, and Center for Research in Human Movement Variability, University of Nebraska at Omaha, Omaha, NE, 68182, USA.
The continued effort to study gait kinematics and the increased interest in identifying individuals based on their gait patterns could be strengthened by the inclusion of data from older groups. To address this need and complement our previous database on healthy young adults, we present an addition to the Nonlinear Analysis Core (NONAN) GaitPrint database. We offer full-body inertial measurement data during self-paced overground walking on a 200 m indoor track of 41 older adults (56 + years old; 20 men and 21 women; age: 64.
View Article and Find Full Text PDFPLoS One
January 2025
Department of Pharmacy, West China Hospital, Sichuan University, Chengdu, China.
There is different administration routes of triamcinolone acetonide (TA) administration for macular edema, but the efficacy ranking remains unclear. The purpose of this study is to assess the efficacy of different administration routes of TA employed in macular edema. PubMed, Medline, Embase, and Cochrane Central Register of Controlled Trials were systematically searched for published articles comparing macular edema in patients with triamcinolone acetonide in different administration.
View Article and Find Full Text PDFDiscov Med
January 2025
Science and Education Department, Zibo Orthopedic Hospital, 255040 Zibo, Shandong, China.
Background: Osteoporotic fractures (OPF) pose a public health issue, imposing significant burdens on families and societies worldwide. Currently, there is a lack of comprehensive and validated risk assessment models for OPF. This study aims to develop a model to assess and predict the risk of OPF in Qingdao City, China.
View Article and Find Full Text PDFBMC Res Notes
January 2025
College of Nursing and Health Sciences, Flinders University, Caring Futures Institute, Adelaide, Australia.
Objective: To present a remodeling of the electroretinogram waveform using a covariance matrix to identify regions of interest and distinction between a control and attention deficit/hyperactivity disorder (ADHD) group. Electroretinograms were recorded in n = 25 ADHD (16 male; age 11.9 ± 2.
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