Refereed journal article or data article (A1)

Effect of dehydration pathway on the surface properties of molecular crystals




List of AuthorsHerzberg M, Zeng G, Mäkilä E, Murtomaa M, Sogaard SV, Garnaes J, Madsen AO, Rantanen J

PublisherROYAL SOC CHEMISTRY

Publication year2021

JournalCrystEngComm

Journal name in sourceCRYSTENGCOMM

Journal acronymCRYSTENGCOMM

Volume number23

Issue number34

Start page5788

End page5794

Number of pages7

eISSN1466-8033

DOIhttp://dx.doi.org/10.1039/d1ce00539a


Abstract
Molecular crystals with water molecules in the crystal lattice (hydrates) can radically change properties if dehydrated. The two most practically relevant pathways of dehydration can be classified as either thermally-induced or solvent-induced. The solid form transformations occurring during these processes are taking place at the surface of the particles either in the solid-gas or solid-liquid interface. In this study, it is demonstrated how atomic force microscopy (AFM) can be used to measure topography, elastic modulus and work function to elucidate differences at the crystal surface depending on the dehydration pathway. These results are performed at a single particle level, so it would be important to link the findings to the bulk powder behaviour. To address this, static charging measurements for bulk powder samples were compared with the single crystal surface measurements. The thermally-induced anhydrate acquired more charge than the monohydrate at the bulk level which could be explained by the increase in work function and surface roughness at a single particle level. The change in sign for the solvent-induced anhydrate was also in agreement with the work function. This underpins the importance of also considering microscale properties, when characterizing nanoscale structures at the surface of particulate systems.


Last updated on 2023-31-03 at 14:55