Negative area compressibility of a hydrogen-bonded two-dimensional material

Abstract

Very few materials expand two-dimensionally under pressure, and this extremely rare phenomenon, namely negative area compressibility (NAC), is highly desirable for technological applications in pressure sensors and actuators.

Nanoscale Metamaterials: Meta-MOFs and Framework Materials with Anomalous Behavior

“…Examples of materials of these topologies featuring NLC include: the archetypal MIL-53 [52], whose breathing transition (see Section 3) is also associated with NLC [47]; the distorted wine rack framework in [NH 4 ][Zn(HCOO) 3 ] MOF [48]; the Zn[Au(CN) 2 ] framework with honeycomb structure [49]; and calcium fumarate trihydrate, a one-dimensional coordination polymer [53]. There is also a know MOF with large negative area compressibility, Zn(CH 3 COO) 2 · 2H 2 O, a hydrogen-bonded 2D supramolecular coordination complex [54] where the NAC arises from cooperative intra-layer coordination and hydrogen-bonding interactions, as well as inter-layer van der Waals forces. Furthermore, like the thermal expansion coefficient, compressibility in MOFs can in principle be tuned by modifications of the framework or inclusion of guest molecules, although reports in that area are still rather scarce.…”

Elastic and hydrostatic behaviour of a zinc dietary supplement, zinc glycinate hydrate

“…A Digital Instrument Multimode SPM in the tapping mode with BRUKER RTESPA-300 tip was used for observing the surface topographies and the corresponding thickness of different exfoliated nanosheets, 17 deposited on a clean silicon substrate (1 Â 1 cm 2 ) by drop casting method. The images were taken at a resolution of 256 Â 256 pixel, by scanning an area of 10 Â 10 mm 2 at a rate of 1.00 Hz.…”

Mechanical properties of coordination polymer-based dietary supplements

“…In terms of composition, CP-based dietary supplements have better bioactivity and less side-effects than conventional purely inorganic food supplements, and play a significant role in the food and pharmaceutical industry [10]. CP-based supplements and additives cover a wide range of materials, including calcium (e.g., calcium gluconate, calcium aspartate, calcium fumarate), copper (e.g., copper glycinate), magnesium (e.g., magnesium malate), zinc (e.g., zinc glycinate, zinc acetate), iron (e.g., ferrous fumarate), and potassium (e.g., potassium citrate) derivatives [9,[11][12][13][14][15].…”

“…However, comparing with the common pharmaceutical molecule drug crystals, food dietary supplements CPs present a significant lack of available knowledge on the elastic and plastic properties. Only few systematic studies involving zinc acetate dihydrate, zinc glycinate hydrate and calcium fumarate trihydrate have been investigated in the literatures [9,14,15]. It is worth noting that many CPs and coordination complexes (e.g., calcium gluconate [28], vitamin B 6 [29] and ferrous fumarate [28,30]) have been served as APIs in tablet form, for example, calcium gluconate (CHCaO) tablet is not only a mineral supplement and medication, but also used as a source of Ca 2+ ion to regulate the drug release with the change in the concentration of calcium gluconate in alginate matrix tablets [31].…”

“…[24], Copyright 2015, American Chemical Society. (c) Zinc and calcium dietary supplements (zinc acetate dehydrate, zinc glycinate hydrate and calcium fumarate trihydrate) [14,15]. Reproduced with permission from Ref.…”