Abstract
Physical properties of alloys are compared as computed from 'direct' and 'inverse' procedures. The direct procedure involves Monte Carlo simulations of a set of local density approximation (LDA)-derived pair and multibody interactions {vf}, generating short-range order (SRO), ground states, order-disorder transition temperatures, and structural energy differences. The inverse procedure involves 'inverting' the SRO generated from {vj} via inverse-Monte Carlo to obtain a set of pair only interactions {ṽf}. The physical properties generated from {ṽf} are then compared with those from {vf}. We find the following: (i) Inversion of the SRO is possible (even when {vf} contains multibody interactions but {ṽf} does not), (ii) Nevertheless, the resulting problem interactions {ṽf} agree with the input interactions {ṽf} only when the problem is dominated by pair interactions. Otherwise, {ṽf} are very different from {vf}. (iii) The same SRO pattern can be produced by drastically different sets {vf}. Thus, the effective interactions deduced from inverting SRO are not unique, (iv) Inverting SRO always misses configuration-independent (but composition-dependent) energies such as the volume deformation energy G(x); consequently, the ensuing {ṽf} cannot be used to describe formation enthalpies or two-phase regions of the phase diagram, which depend on G(x).
Original language | English (US) |
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Pages (from-to) | 519-523 |
Number of pages | 5 |
Journal | Solid State Communications |
Volume | 101 |
Issue number | 7 |
DOIs | |
State | Published - Feb 1997 |
Keywords
- A. Disordered systems
- D. Order-disorder effects
- D. Thermodynamic properties
ASJC Scopus subject areas
- Chemistry(all)
- Condensed Matter Physics
- Materials Chemistry