A formula for the calculation of the number of Wyckoff sequences of a given length is presented, based on the combinatorics of multisets with finite multiplicities and a generating function approach, assuming a certain space-group type and taking into account the number of non-fixed and fixed Wyckoff positions, respectively. The formula is applied to the 44 distinguishable combinatorial types of the 230 space-group types. A comparison is made between the calculated frequencies of occurrence of Wyckoff sequences of given space-group type and length and the observed ones for actual crystal structures, as retrieved from the Pearson's Crystal Data Crystal Structure Database for Inorganic Compounds.

Download full-text PDF

Source
http://dx.doi.org/10.1107/S2053273321013565DOI Listing

Publication Analysis

Top Keywords

wyckoff sequences
12
crystal structures
8
number wyckoff
8
sequences length
8
space-group type
8
combinatorics crystal
4
structures number
4
wyckoff
4
length formula
4
formula calculation
4

Similar Publications

Article Synopsis
  • The study aimed to understand the genetic factors of prostate cancer by analyzing 14 genes linked to cancer susceptibility using Next Generation Sequencing (NGS).
  • Key findings revealed pathogenic mutations in genes like BRCA1, BRCA2, and TP53, along with benign variations, highlighting their differing roles in cancer progression.
  • Functional tests showed that mutations in BRCA1 and BRCA2 were linked to lower expression levels and increased sensitivity to certain chemotherapy drugs, while mutations in TP53 did not notably affect drug response.
View Article and Find Full Text PDF

In September 2021, eight campylobacteriosis cases were identified in a town in Nebraska, USA. We assessed potential exposures for a case-control analysis. We conducted whole-genome sequencing on Campylobacter isolates from patients' stool specimens.

View Article and Find Full Text PDF
Article Synopsis
  • - The TRAP (Twin Reversed Arterial Perfusion) sequence occurs in monochorionic pregnancies where one fetus is healthy and the other is non-viable, leading to risks like high-output cardiac failure in the viable twin.
  • - A 32-year-old woman with TRAP syndrome experienced contractions and spotting at 26 weeks and underwent a cesarean section after concerns of placental abruption; her viable twin was born but later died due to prematurity complications.
  • - This case emphasizes the need for early detection and ongoing prenatal care in managing TRAP syndrome, while also calling for more research into interventions that improve outcomes for affected pregnancies.
View Article and Find Full Text PDF

Synthesis, Physical, and Magnetocaloric Properties of MgZn-Type GdAlRh.

Inorg Chem

July 2024

Institut für Anorganische und Analytische Chemie, Universität Münster, Corrensstraße 30, 48149 Münster, Germany.

GdAlRh was synthesized from the elements using arc-melting techniques, along with subsequent annealing. The title compound adopts the hexagonal MgZn type structure (space group 6/, 12, Wyckoff sequence ) with the Gd atoms found on the Mg positions (4), the Rh (2) and Al (6) atoms occupying the two Zn sites of the prototype. In addition, mixing of Rh and Al on both crystallographic positions is observed.

View Article and Find Full Text PDF

Three polyanionic tellurides, BaCuTe ( = K, Rb, Cs), were synthesized in salt flux. The isostructural tellurides crystallize in a new structure type, in the cubic 3 space group with a Wyckoff sequence of and large unit cell volumes of over 5500 Å. The structures feature a framework of [CuTe] tetrahedra and [CuTe] trigonal pyramids with disorder in the Cu sites.

View Article and Find Full Text PDF

Want AI Summaries of new PubMed Abstracts delivered to your In-box?

Enter search terms and have AI summaries delivered each week - change queries or unsubscribe any time!