Spectroscopy and Spectrophotometry are terminologies differing with respect to the approach and purpose of the study of light-matter interactions, the former implies a more theoretical approach, the purpose being to obtain structural and related property information through the spectral data collection.

Spectrophotometry on the other hand deals with a more quantitative approach to the problem, here the spectral information is used to quantify one or more components in the substance under analysis.

Dear Nagib A.S. Qarah ,

I hope this can be useful for you:

You can think of Spectrometry as general study of interaction of matter with electromagnetic waves (the whole spectra). While Spectrophotometry is the quantitative measurement of light spectra reflection and transmission properties of materials as function of the wavelength.

Note from first principle perspective you need to have the former for the latter. Think of the former as the foundational component (the physics),and the latter an application of the former for a specific subject of measurement.

For a detailed explanation, please refer to this link:

https://socratic.org/questions/what-is-difference-between-spectrophotometry-and-spectroscopy

All the best

Hi Nagib,

spectroscopy is a group of physical methods that decompose radiation according to a certain property such as wavelength, energy, mass, etc. The resulting intensity distribution is called spectrum.

Spectrometry is the quantitative measurement of spectra using a spectrometer. The recording method is called spectrography and the recording (graphical representation) itself is called spectrogram, but in technical jargon it is often simply called "the spectrum".

Regards

Markus

Spectroscopy measures emission spectrum at different wavelengths while spectrophotometry measures relative intensity of light at a specific wavelength .

Spectroscopy implies the study of physics part of the interaction of mater with electromagnetic wave of different wavelength. Spectrophotometry is the measurement of spectra for qualitative or quantitative analysis emitting species.

According to the latest answers on our question, the assays using uv-visible are spectroscopy or not?

I agree with Markus.

Dear Nagib A.S. Qarah

Spectroscopy is the measurement of light (IR, Visible, UV, X-ray ).

Spectrometry is measuring things that are not light (like ions in mass spectroscopy).

So according to above the Spectroscopy is the true in your assays

Even though radio waves and gamma rays are on the electromagnet spectrum, they are usually referred to as spectrometry (like NMR).

There’s also spectrophotometer, which quantitative measurement of color.

Spectrometer

A spectrometer is a tool that scientists use to gather information about a substance based on the visible, ultraviolet or infrared light that it projects, and can be used in different fields of science. For example, astronomers use spectrometers to find the temperature of an object in space, gauge the speed that it is traveling and even estimate the object's weight. Scientists also use spectrometers to determine the composition of items on Earth or in space. This includes the elemental components of items. Scientists in the medical field often use spectrometers to identify contaminants, toxins in the bloodstream or even diseases.

Spectrophotometer

A spectrophotometer is a device that is used to measure the intensity of electromagnetic radiation at various wavelengths. Spectrophotometers are used to measure the absorbency of a certain wavelength of a solution, reflectance of solutions, transmittance or the transparency of solids. In addition, they also measure the diffusivity of the light ranges in electromagnetic radiation spectrum that covers about 200nm to 2500nm with different calibrations and controls. There are two basic classifications of spectrophotometer. The first type is a double-beam spectrophotometer, which compares the intensity of light between one reference light path, and the substance that is being measured. The second type measures the relative light intensity of the beam prior to and after the test sample is introduced.

Spectroscopy deals with the transitions induced in a chemical species by its interaction with the photons of electromagnetic radiation.

Spectrophotometry is a quantitative approach of measuring the relative energy i.e. emitted, transmitted or reflected in the visible or UV regions as a function of wave length or wave number.