The binary / unformatted form of the Stanjan thermo file carries the extension ".sud" (Stanjan Unformatted Data). It can not be read with an ordinary text editor. The storage format for each species consists of a list of variables, as follows: chemf,ref,wmf,dhf0f,ithlf,dcsf,6(narf,atomrf),ithmf,60(s0f),60(hmh0f) where: NAME Type Meaning chemf - character*8 species name ref - character*8 reference/date wmf - real molecular weight (g/mol) dhf0f - real heat of formation (298.15 K) (kcal/mol) ithlf - integer Tmin/100 (K) for valid data dcsf - real density (g/cc) for condensed species, 0 for gases narf - integer number of atoms of 6 types atomrf - character*2 names of 6 atom types ithmf - integer Tmax/100 (K) for valid data s0f - real entropy (1 atm) (cal/mol-K) for 60 temperatures hmh0f - real enthalpy difference between 60 temperatures and 298.15 K (kcal/mol) Each character is represented by a single byte, and each integer and real number is represented by four bytes, although this may depend on the characteristics of the platform on which the file is generated. This format suffers from some significant disadvantages (the first two are shared by the formatted text version): 1. The use of tabulated data is inefficient, relative to polynomial fits. 2. Since tabulated values are inherently limited to the temperature range 200 - 6000 K, data outside this range can not be represented or used. Most problems fall within this range, so this is not normally a severe limitation. On the other hand, since the file space is allocated for the entire range, data that could be used to increase precision over a narrower range is wasted on irrelevant temperatures. 3. Binary files generally do not transfer well between different platforms or operating systems. SUD files generated on one computer are usually not usable on different types of computers. 4. Binary files can not be read or edited by standard text editors. The main advantage of this format is file size, which is smaller for the same amount of data. Given the cheapness of storage space (relative to when Stanjan was originally written), this is not usually a concern. A special version of the Stanjan unformatted file format has been devised to allow the use of high (extended) temperature polynomial coefficients. The same data fields are used, but with different meanings in some cases: s0f(1) - negative (to indicate that the alternate data form is being used) number of temperature intervals s0f(2) - minimum temperature for valid data s0f(3) - maximum temperature for valid data s0f(4) - number of terms in cp0 equation s0f(5..12) - 8 temperature exponents for cp0 equation (though only 7 used?) s0f(13..23, etc.) - same as 2..12 for additional temperature intervals hmh0f(1..8) - 8 coefficients for cp0 equation hmh0f(9) - b1 integration constant for enthalpy equation hmh0f(10) - b2 integration constant for entropy equation hmh0f(11..20) - same as 1..10 for additional temperature intervals