Abstract
Intramolecular and/or intermolecular hydrogen-bonded maleate (HMA -) monoanions were introduced into cation radical salts of tetrathiafulvalene (TTF), forming three kinds of crystals: (TTF +)(H2MA)(HMA -) (1), (TTF +) 3(HMA -) 3(CH 3OH)(H 2O) 0.5 (2), and (TTF +) 3(TTF 0) 5(HMA -) 3 (3). In crystals 1 and 2, the monovalent TTF + cation formed a strong π-dimer of (TTF +) 2 and a π-trimer of (TTF +) 3, respectively. In crystal 3, a non-uniform π-stack of TTF 0 and TTF + was formed, which was further surrounded by neutral TTF through S⋯S and S⋯π interactions, forming a cylindrical TTF 0 array around the π-stack. A charge-separated electronic state of (TTF +) 3(TTF 0) 5(HMA -) 3 in crystal 3 was observed in the Raman spectra. Crystal 3 showed a semiconducting temperature dependent behavior with a room temperature conductivity of 3 × 10 -3 S cm -1, which was six orders of magnitude higher than those of crystals 1 and 2. The protonated state of the (H2MA)(HMA -) anion in crystal 1 was representative of an (HMA -⋯H +⋯HMA -) dimer, where the bridging proton between the two HMA - anions was located at the midpoint between the two oxygen sites. A very strong intramolecular symmetrical O-H⋯O - hydrogen-bonding interaction was observed in crystals 1-3 according to potential energy calculations of proton coordination in the O-H⋯O - hydrogen bonding.
| Original language | English |
|---|---|
| Pages (from-to) | 3875-3881 |
| Number of pages | 7 |
| Journal | CrystEngComm |
| Volume | 14 |
| Issue number | 11 |
| DOIs | |
| Publication status | Published - 2012 Jun 7 |
ASJC Scopus subject areas
- Chemistry(all)
- Materials Science(all)
- Condensed Matter Physics