Effect of Pressure onfNumber and Isomer Shift forFe57in Cu, V, and Ti

The effect of pressure to 100 kbar on the Mössbauer resonance has been measured for ${\mathrm{Co}}^{57}$ (${\mathrm{Fe}}^{57}$) in Cu, V, and Ti. Using Bridgman anvils, it is possible to establish the $f$ number as a function of pressure. For Cu the characteristic temperature $\theta$ calculated in this way compares closely with that obtained from x-ray Bragg line intensities or room-temperature specific heats. For Ti the comparison with room-temperature specific-heat data is good. For V the $\theta$ we obtain compares closely with low-temperature specific-heat values for impure samples, but is low compared with values obtained on very pure samples. The isomer-shift changes with pressure are analyzed briefly in terms of $4s-3d$ electron transfer.