---
name: "sigeps"
section: "1"
platform: "linux"
package: "gromacs-data"
version: "4.0.7-3"
release: "Debian 6.0 (Squeeze)"
platforms: ["linux"]
url: "https://new.carta.tech/sigeps"
---

# sigeps(1)

convert c6/12 or c6/cn combinations to and from sigma/epsilon VERSION 4.0.1

## NAME

sigeps - convert c6/12 or c6/cn combinations to and from sigma/epsilon

**VERSION 4.0.1**

## SYNOPSIS

**sigeps** **-o** *potje.xvg*  **-\[no\]h** **-nice** *int*  **-\[no\]w** **-\[no\]xvgr** **-c6** *real*  **-cn** *real*  **-pow** *int*  **-sig** *real*  **-eps** *real*  **-A** *real*  **-B** *real*  **-C** *real*  **-qi** *real*  **-qj** *real*  **-sigfac** *real*

## DESCRIPTION

Sigeps is a simple utility that converts c6/c12 or c6/cn combinations to sigma and epsilon, or vice versa. It can also plot the potential in  file. In addition it makes an approximation of a Buckingham potential to a Lennard Jones potential.

## FILES

**-o** *potje.xvg* **Output**\
  xvgr/xmgr file

## OTHER OPTIONS

**-\[no\]h***no*    \
  Print help info and quit

**-nice** *int* **0**\
  Set the nicelevel

**-\[no\]w***no*    \
  View output xvg, xpm, eps and pdb files

**-\[no\]xvgr***yes*   \
  Add specific codes (legends etc.) in the output xvg files for the xmgrace program

**-c6** *real* **0.001** \
  c6

**-cn** *real* **1e-06** \
  constant for repulsion

**-pow** *int* **12**\
  power of the repulsion term

**-sig** *real* **0.3**   \
  sig

**-eps** *real* **1**     \
  eps

**-A** *real* **100000**\
  Buckingham A

**-B** *real* **32**    \
  Buckingham B

**-C** *real* **0.001** \
  Buckingham C

**-qi** *real* **0**     \
  qi

**-qj** *real* **0**     \
  qj

**-sigfac** *real* **0.7**   \
  Factor in front of sigma for starting the plot

## SEE ALSO

**[gromacs(7)](/gromacs/7.md)**

More information about **GROMACS** is available at \<*http://www.gromacs.org/*\>.