This file briefly describes the utility programs VIEW.EXE,
CONE.EXE and VEC.EXE.

                                    CONE
                                    ====
CONE calculates shadow cones for binary atomic collisions. CONE
gets its atomic data either from the file ELEMENT or from the
terminal. You can edit ELEMENT to suit your needs.

CONE will output the (x,y) coordinates which define the shadow
cone envelope. Alternatively, CONE will output the critical
angle corresponding to a specified interatomic separation
(d = [x+y]), as in a conventional impact collision ISS experiment.

Cone Options:
cone     - interactively output Rc (y) for specified l (x).
cone /l  - write (l,Rc) output to file 'cone.dat'.
cone /d  - write (d,c) output to file 'cone.dat'.

Cone uses the ZBL potential to describe the projectile-target
interaction. The Runge-Kutta algorithm is used for integration.
At the conclusion, CONE outputs the energy error which is generally
very, very small as these calculations are very accurate.

CONE was the basis of our paper in: Nucl. Instrum. Methods
B73 (1993) 163-171, to which the reader is referred.

                                   VIEW
                                   ====
The purpose of VIEW is to provide a visual representation of the various
files created by SPIDER and WINNOW, namely TRG, IMP, SPL and DAT files.
The file loading operation can be initiated from the command line or
from the menu.

Only one file can be displayed in each window, but you may have several
windows open. This program runs under DOS real mode, so it is subject
to memory limitations.

Once you have a file loaded, you have various options for looking at
it. VIEW is most flexible with TRG files, since it allows you to
examine them in 3D.

You can shift an image around on the screen with the arrow keys.
You can rotate it around an axis in space using the bottom row
of buttons ('Reverse' reverses the sense of the rotation). The
image can be viewed as a projection on the xy, xz, or yz planes.
The zoom controls allow you to zoom into or out of the image. A
menu bar in the bottom right corner of each display window has
options for modifying the display e.g. to display sphere-like
points of various radii and colours.

Normally VIEW is invoked by SPIDER as it is needed, but you can also
run it as a standalone program. I hope its use is intuitive.

                                  VEC
                                  ===
VEC is a utility which carries out various simple calculations involving
vector quantities. It is included for its relevance to crystallographic
calculations. For example, what is the angle between the [110] and
the [121] direction? What are the angular coordinates of the [111]
direction?
VEC computes various relations based on unary (1 vector), binary (2 vector)
or ternary (3 vector) inputs (u,b,t options respectively). The user
just specifies the vectors in the format X Y Z i.e. numbers with
spaces between them.
You can try it out - I imagine the output won't require much
explanation. The binary vector relations are the most used in the
lab: one of the vectors is your surface orientation (e.g. 1 1 1 for
Cu(111) ), while the other vector is the one whose relative
orientation you'd like to know. 




