The crystal structure and bonding environment of K_{2}Ca(CO_{3})_{2}bütschliite were probed under isothermal compression via Raman spectroscopy to 95 GPa and single crystal and powder Xray diffraction to 12 and 68 GPa, respectively. A second order BirchMurnaghan equation of state fit to the Xray data yields a bulk modulus,
Initially, vanadium dioxide seems to be an ideal firstorder phase transition case study due to its deceptively simple structure and composition, but upon closer inspection there are nuances to the driving mechanism of the metalinsulator transition (MIT) that are still unexplained. In this study, a local structure analysis across a bulk powder tungstensubstitution series is utilized to tease out the nuances of this firstorder phase transition. A comparison of the average structure to the local structure using synchrotron xray diffraction and total scattering pairdistribution function methods, respectively, is discussed as well as comparison to bright field transmission electron microscopy imaging through a similar temperatureseries as the local structure characterization. Extended xray absorption fine structure fitting of thin film data across the substitutionseries is also presented and compared to bulk. Machine learning technique, nonnegative matrix factorization, is applied to analyze the total scattering data. The bulk MIT is probed through magnetic susceptibility as well as differential scanning calorimetry. The findings indicate the local transition temperature (
 NSFPAR ID:
 10370508
 Publisher / Repository:
 Nature Publishing Group
 Date Published:
 Journal Name:
 Scientific Reports
 Volume:
 12
 Issue:
 1
 ISSN:
 20452322
 Format(s):
 Medium: X
 Sponsoring Org:
 National Science Foundation
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