For Research/Education: Quantitative Analysis/Mixed Layer Clay Interpretation

About Newmod II and Wildfire

Calculation of X-Ray Diffraction Patterns Of Mixed-Layer Clay Minerals

Newmod II is an up​dated version (MS Windows) of the original Newmod by Dr. Robert C. Reynolds Jr. is an integrated package for calculating

one-dimensional diffraction patterns for mixed-layer clay miner​als, mixing calculated patterns to simulate natural samples for quantitative

 analysis, plotting patterns to different scales, and measuring d, 2Ø, integrated areas, and peak widths at half maximum height.

Wildfire is an updated version (JAVA language) of the original written by Dr. Reynolds. It is an integrated package that calculates three-dimensional powder X-ray diffraction patterns for mica poly types and their disordered variations. It contains many of the plotting features of Newmod.

Newmod II


NEWMOD II is computationally fast and easy to operate. It is  menu driven and all parameters are entered by means of buttons or  sliding bars, though optionally, some can be entered by typing. The  program operates in real time and in a continuous simulation mode so  there is not waiting between input and output. This means you can  generate, for example, a real-time animated series of patterns for a  specific illite/smectite mineral in which the Fe content is continuously  changed by moving the GUI Fe slider control.

NEWMOD  II can, by varying some parameters numerically fit the simulated  (theoretical) pattern to an experimentally derived one. The experimental  pattern can be entered into Newmod in a variety  of ASCII/TXT formats. The program takes care of odd or uneven 2Ø step sizes generated by some diffractometers by interpolating to the standard Newmod values of .01, .02, .05, .1, .2 or .5.

NEWMOD  II can calculate a theoretical pattern made by mixing up to eight other  patterns (phases) in different percentages. A numerical optimization  can be run to  fit the mixed pattern to the observed by  automatically  adjusting these percentages.

NEWMOD  II is a new version of the original NEWMOD. It utilizes the  same algorithms developed by Dr. Robert C. Reynolds of Dartmouth College  but with features that make it more powerful and user-friendly than the old windows version. It has been successfully tested for MS Windows 10 (32 and 64 bit). 



Calculates three-dimensional  X-ray diffraction patterns for randomly oriented mica (illite) and  illite/smectite (I/S) powders with various  types and quantities of rotational disorder and composed of two types of  randomly interstratified silicate layers.

Intensities are computed by a three-dimensional integration in the reciprocal space construct of Brindley and Méring (1951). 

The program is written in standard Java and is  menu driven like Newmod where all parameters are entered by means of  buttons or sliding bars, though optionally, some can be entered by  typing.



Newmod & Wildfire

 1526 Farlow Avenue, Crofton, Maryland 21114