Introduction


Raman effect is first discovered by C.V. Raman and K.S Krishan in 1928. When a sample exposes monochromatic light, the sample absorbs the light, visual portion of light gets transmitted to the sample. However, a minor part of the light is scattered by the sample in all direction. Incident light has a particular frequency, if scattering light has frequency same as incident light, the scattering is called Rayleigh scattering. It has been observed that about 1% of total scatter intensity occurs frequency different from incident frequency, this is called Raman scattering. Raman scattering can be called a two photon process, an electron has different vibrational levels, they are defined by different specific energy differences.


When an incident molecular light interacts with an electron in the sample, an electron absorbs energy from an incident photon. It strikes the state of virtual energy, the energy transform is given by a formula, the electron falls back to energy level by losing energy. If energy loss equals the energy of the incident photon. An electron falls back to an initial level, and if this process emits another photon, since the energy loss equal value same frequency of the incident photon, as the frequency is same, Rayleigh scattering occurs. However, sometimes electron loss energy from virtual state to fall back to different vibration level. In this case, energy loss by the electron is different, and the energy absorbed from incident photon, as a result, photon emitted, the photon has energy different from incident photon, it's possible when the frequency of emitted photon is different from the frequency of incident photon, this gives right to Raman scattering, depends on final energy of electron or final vibrational of electron, Raman scattering can be separated into two, stock lines and anti-stocks lines.


If the frequency of scattering photon less than the frequency of the incident photon, stocks lines is observed on Raman spectra. It happens when an electron absorbs energy, Similarly, If frequency If scattering photon greater than the frequency of the incident photon, anti-stocks lines is observed, this means the energy released by the electron. Raman spectra give a molecular fingerprint, different molecules have different Raman spectra, By studying spectra, one can identify rotational levels and, it helps to perform analysis of qualitative, similarly, the intensity of particular Raman lines help determine the concentration of molecule in a sample, In this manner, quantitive analysis can be done. Thus Raman spectroscopy can be used as both qualitative and quantitative analysis tool. Raman Instrument has a complete line of handheld Raman Analyzer, Portable Raman Spectrometer, Raman Microscope, Educational Raman System etc.

The generation of a Raman spectrum begins with an excitation laser, routed to the sample via a Raman probe. Scattered Raman light is collected by the probe and measured by a spectrometer with the sensitivity and Raman shift range suitable for your application. Complete the system with a sample holder that accepts cuvettes, probes or SERS substrates, plus software and laser safety glasses.At the heart of each modular Raman setup is the spectrometer. Options range from our high-performance ATP6500 Scientific-Class spectrometer to the recently introduced 1064nm NIR Raman spectrometer, a more accessible option for budget-conscious researchers and product integrators.

Modular Raman