G94 cube file units and Cerius2

     Dear computational chemists,
      I have a question concerning electron density surfaces
 calculated with G94 (cube=density), the use of Cerius2 to
 display these surfaces and units.
      According to the cube file I have calculated, the density
 values range from 0 to 27 electrons/bohr^3 (I think). When I
 use the Gaussian interface in Cerius2 to display the surface,
 the property range displayed is 0 to 182. Using the conversion
 factor between electrons/bohr^3 and electrons/angstrom^3 (6.75),
 I get the the property range displayed in Cerius2. To make sure
 this was correct, I created a 3X3X3 cube with only one non-zero value, namely
 When I display this cube in Cerius2, I expected the property to range
 from 0 to 6.75 e/A^3. I get that the range is 0 to 1.0. Further, I am
 able to display electron density values between 0.0 and 1.0.
     Are the values in the cube file multiplied by a conversion factor
 or are values extra/intrapolated?
    I have also the same question for the electrostatic potential for which
 there is also a difference the cube file values and the displayed
    I will summarize.
    Thank you for your help.
 | Nathalie Godbout                           |
 | University of Illinois at Urbana-Champaign |
 | 600 S. Goodwin Av. Box 23.6                |
 | Urbana, IL 61801                           |