Phonon density-of-states and related thermodynamic properties of the α-quartz-type and rutile-type germanium dioxide (GeO2) are investigated from density functional perturbation theory. The significant density-of-states at the low frequencies in the α-quartz-type GeO2 are at the origin of (i) its lower internal energy below 250 K, (ii) its smaller free energy, (iii) its higher entropy, (iv) its lower Debye temperature and (v) its larger positive linear thermal expansion, with respect to the rutile-type GeO2.
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http://dx.doi.org/10.1039/c3cp52741g | DOI Listing |
Phys Rev Lett
December 2024
RIKEN, Condensed Matter Theory Laboratory, CPR, Wako, Saitama 351-0198, Japan.
We show that the ground-state expectation value of twisting operator is a topological order parameter for U(1)- and Z_{N}-symmetric symmetry-protected topological (SPT) phases in one-dimensional "spin" systems-it is quantized in the thermodynamic limit and can be used to identify different SPT phases and to diagnose phase transitions among them. We prove that this (nonlocal) order parameter must take values in Nth roots of unity, and its value can be changed by a generalized lattice translation acting as an N-ality transformation connecting distinct phases. This result also implies the Lieb-Schultz-Mattis (LSM) ingappability for SU(N) spins if we further impose a general translation symmetry.
View Article and Find Full Text PDFPhys Rev Lett
December 2024
Duke University, Department of Physics, Durham, North Carolina 27708, USA.
The emergence of a quantum spin liquid (QSL), a state of matter that can result when electron spins are highly correlated but do not become ordered, has been the subject of a considerable body of research in condensed matter physics [1,2]. Spin liquid states have been proposed as hosts for high-temperature superconductivity [3] and can host topological properties with potential applications in quantum information science [4]. The excitations of most quantum spin liquids are not conventional spin waves but rather quasiparticles known as spinons, whose existence is well established experimentally only in one-dimensional systems; the unambiguous experimental realization of QSL behavior in higher dimensions remains challenging.
View Article and Find Full Text PDFArch Microbiol
January 2025
College of Life Sciences, Fujian Agriculture and Forestry University, Fuzhou, 350002, People's Republic of China.
Lyophyllum decastes is a type of edible and medicinal mushroom with high nutritional value. However, it can be infected by fungi during the fruiting process, which impairs the development of the industry. In this study, one pathogenic fungus was isolated from the diseased fruiting bodies of L.
View Article and Find Full Text PDFFood Chem X
January 2025
Joint International Research Laboratory of Agriculture and Agri-Product Safety of the Ministry of Education of China, Institutes of Agricultural Science and Technology Development, Yangzhou University, Yangzhou 225009, China.
Green electrospinning for the production of freshness-indicating labels, employing entirely natural biopolymers and pigments, holds significance in the development of intelligent food packaging. This study aimed to prepare zein (Z) fibrous film (FF) incorporated with varying concentrations of anthocyanin (A; 0-0.5 %) through green electrospinning.
View Article and Find Full Text PDFJ Am Chem Soc
January 2025
Center for Sustainable Catalysis and Engineering, KU Leuven, Celestijnenlaan 200F, Leuven 3001, Belgium.
The local environment of the active site, such as the confinement of hydronium ions within zeolite pores, significantly influences catalytic turnover, similar to enzyme functionality. This study explores these effects in the hydrolysis of guaiacols─lignin-derived compounds─over zeolites in water. In addition to the interesting catechol products, this reaction is advantageous for study due to its bimolecular hydrolysis pathway, which involves a single energy barrier and no intermediates, simplifying kinetic studies and result interpretation.
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