TY - JOUR
T1 - Cation mobility and structural changes on the water removal in zeolite-like zinc hexacyanometallates (II)
AU - Avila, M.
AU - Rodríguez-Hernández, J.
AU - Lemus-Santana, A. A.
AU - Reguera, E.
N1 - Funding Information:
This research was partially supported by the Projects ICyTDF-PIFUTP08-158 and CONACyT 123480. Access to the LNLS synchrotron radiation facility (at Campinas, Brazil) is also acknowledged.
PY - 2011/8
Y1 - 2011/8
N2 - The cation (A) mobility and structural changes on the water molecules removal in zeolite-like zinc hexacyanometallates series, Zn3A 2[Fe(CN)6]2·xH2O with A=Na, K, Rb and Cs, were studied from X-ray diffraction data recorded for hydrated and anhydrous samples at room temperature and at 77 K. The crystal structure for the anhydrous phases were solved and refined and then compared with those corresponding to their hydrated form. On the water molecules removal the charge balancing cation (A) migrates to favor a stronger interaction with the N ends of the CN bridges where the framework negative charge is located. This cationframework interaction model is supported by the recorded IR spectra for both hydrated and anhydrous samples. The new cation position induces distortion for both the cavity shape and their windows and also leads to cavity volume reduction. This is relevant for the properties of this family of solids as porous materials and their behavior in adsorption and separation processes, among them for hydrogen storage.
AB - The cation (A) mobility and structural changes on the water molecules removal in zeolite-like zinc hexacyanometallates series, Zn3A 2[Fe(CN)6]2·xH2O with A=Na, K, Rb and Cs, were studied from X-ray diffraction data recorded for hydrated and anhydrous samples at room temperature and at 77 K. The crystal structure for the anhydrous phases were solved and refined and then compared with those corresponding to their hydrated form. On the water molecules removal the charge balancing cation (A) migrates to favor a stronger interaction with the N ends of the CN bridges where the framework negative charge is located. This cationframework interaction model is supported by the recorded IR spectra for both hydrated and anhydrous samples. The new cation position induces distortion for both the cavity shape and their windows and also leads to cavity volume reduction. This is relevant for the properties of this family of solids as porous materials and their behavior in adsorption and separation processes, among them for hydrogen storage.
KW - A. Microporous Materials
KW - B. Crystal Growth
KW - C. X-ray diffraction
KW - D. Crystal structure
UR - http://www.scopus.com/inward/record.url?scp=79959568291&partnerID=8YFLogxK
U2 - 10.1016/j.jpcs.2011.05.012
DO - 10.1016/j.jpcs.2011.05.012
M3 - Artículo
SN - 0022-3697
VL - 72
SP - 988
EP - 993
JO - Journal of Physics and Chemistry of Solids
JF - Journal of Physics and Chemistry of Solids
IS - 8
ER -