# ARTS built-in documentation server

## Workspace Method complex_refr_indexWaterVisibleNIRHarvey98

### Description

Refractive index of water and steam for the optical and near infrared.
Refractive index as function of temparature, frequency and density.
It is limited only to the real part. The imaginary part is 0.
From:
Revised formulation for the Refractive Index of Water and Steam as a Function
of Wavelength, Temperature and Density
Journal of Physical and Chemical Reference Data 27, 761 (1998),
https://doi.org/10.1063/1.556029 27, 761
see also http://www.iapws.org/release.html or https://www.nist.gov
Range of validity:
271.15K < temperature < 773.15K
0 kg m^-3 < density < 1060 kg m^-3
157.785504THz < frequency < 1498.96229THz or 0.2µm < wavelength < 1.9µm
Density can be set as Vector of size 1 or it must have the same size as
as data_t_grid.
IMPORTANT: Though the output is complex_refr_index, it only contains
the real part. The imaginry part is zero.

**Authors: **Manfred Brath

### Synopsis

complex_refr_indexWaterVisibleNIRHarvey98( | complex_refr_index, data_f_grid, data_t_grid, density_water, only_valid_range ) |

### Variables

OUT+IN | complex_refr_index | (GriddedField3) | Complex refractive index (n) data. |

GIN | data_f_grid | (Vector) | Frequency grid for refractive index calculation |

GIN | data_t_grid | (Vector) | Temperature grid for refractive index calculation |

GIN | density_water | (Vector) | Density of water |

GIN | only_valid_range | (Index, Default: 1) | Flag. If true refractive index is calculated only
within range of validity and it will throw an error if outside
range of validity.
If false no check is made, so use at your own risk. |