The stability and vibrational spectra of three-ring containing zeolitic silica polymorphs

A.J.M. Man, de, S. Ueda, M.J. Annen, M.E. Davis, R.A. Santen, van

Research output: Contribution to journalArticleAcademicpeer-review

13 Citations (Scopus)
21 Downloads (Pure)

Abstract

Zeolitic silica polymorphs contg. three-membered rings are modeled using three different atomistic potential sets for lattice energy minimization calcns. of their structure and using a general valence force field to calc. vibrational spectra. In some cases, large deviations from the exptl. symmetry occur upon energy minimization. The lattice energy calcns. show that structures with tetrahedra that participate in one or two three-rings can exist in the pure silica form. A hypothetical structure in which all tetrahedrally coordinated atoms are part of a three ring, and with a corresponding very low framework d., is significantly less stable. The calcd. vibrational spectra are very sensitive to small-scale structural features like bond lengths and bond angles. Because three-ring structures generally have small Si-O-Si angles compared with other zeolites, relatively low-frequency asym. stretch modes are predicted. No specific spectral peak can be assigned to a three-ring mode. The differences in structural detail computed using the three potential sets for silica product variations in predicted IR spectra that are larger than found between different structural polymorphs. This indicates the need for further improvement of potential parameters applicable to structure relaxation
Original languageEnglish
Pages (from-to)789-800
JournalZeolites
Volume12
Issue number7
DOIs
Publication statusPublished - 1992

Fingerprint Dive into the research topics of 'The stability and vibrational spectra of three-ring containing zeolitic silica polymorphs'. Together they form a unique fingerprint.

  • Cite this