University of Surrey

Test tubes in the lab Research in the ATI Dance Research

An unusual phase transition in the crystal structure and physical properties of (TTF)[MO(CN)]·4HO, where TTF = tetrathiafulvalene

Rombaut, G, Turner, SS, Le Pévelen, D, Mathonière, C, Day, P and Prout, K (2001) An unusual phase transition in the crystal structure and physical properties of (TTF)[MO(CN)]·4HO, where TTF = tetrathiafulvalene Journal of the Chemical Society, Dalton Transactions (22). pp. 3244-3249.

[img] Text
2001 Dalton 3244.pdf
Restricted to Repository staff only

Download (237kB)


At 270 K, the charge transfer salt(TTF)[Mo(CN)]·4H O,I, crystallizes in the triclinic space group P1̄ with a = 9.9094(2), b = 10.6781(2), c = 23.6086(7) Å, a = 75.7910(8), β = 88.6010(9), γ = 78.5250(8)°, V = 2372.5(1) Å and Z = 2. At 120 K, the space group is unchanged with a = 9.7990(7), b = 10.6630(5), c = 22.9940(2) Å, a = 79.981(4), β = 89.798(4), γ = 79.013(4)°, V = 2321.5 Å and Z = 2. On comparing the two sets of data, we see significant changes in the cell parameters, most notably in the angle a. Variable temperature crystallographic studies indicate a first order phase transition accompanied by hysteresis, which corresponds to a change in the transport properties.I is a semiconductor and the high temperature activation energy of 0.06 eV changes sharply to 0.15 eV below 236 K. Bulk magnetic susceptibility and ESR measurements indicate that the TTF molecules are antiferromagnetically coupled. The temperature dependence of the EPR spectrum changes from 300-200 K, in approximate agreement with the transport and structural results. The optical spectrum of (TTF)[Mo(CN)]·4HO consists of several broad bands assigned to TTF charged molecules, to [Mo(CN)] and to charge transfer from the donors to the acceptor in the near infra-red range. Preliminary magnetic susceptibility measurements under light irradiation with a multi-line (752.5-799.3 nm) laser were also performed, but no photomagnetic effect was noted.

Item Type: Article
Authors :
Rombaut, G
Turner, SS
Le Pévelen, D
Mathonière, C
Day, P
Prout, K
Date : 2001
Depositing User : Symplectic Elements
Date Deposited : 28 Mar 2017 13:22
Last Modified : 31 Oct 2017 15:14

Actions (login required)

View Item View Item


Downloads per month over past year

Information about this web site

© The University of Surrey, Guildford, Surrey, GU2 7XH, United Kingdom.
+44 (0)1483 300800