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How to pronounce emission spectrum in English?

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[Music]
hey guys
presses here in this video we'll be
learning about the experimental design
of the first experiment in CNG 292 so by
the end of this video you'll be able to
differentiate between the emission
spectrum and the excitation spectrum
first of all let's take a look at the
emission spectrum the instrumental setup
of a first spectroscopy is pretty simple
first we have our sample in a quat cell
and then on one side we have the
excitation sauce the detector is usually
placed at the right angle to the
incident beam of the excitation sauce
this is to prevent the detector from
capturing the incident light because
what we are interested here is the
emission of our sample of our first
sample the process compound that we
interested in this particular Hartmann
is creamy so when we exhale a sample
with the excitation sauce cleaning
molecule at the ground state will be
promoted to the first excited state and
within this first excited state we have
different vibrational energy levels okay
once the Queenie molecule have been
excited from the ground state to the
first excited state you undergoes a
series of non radiative vibrational
relaxation and drop back down to the
lowest vibrational energy level of the
first excited state then you undergo a
radiative relaxation in this case this
will be the first and this will be the
emission that will be capturing with our
detector so this is what we corner for
our sense okay
let's go foresters right he's actually
emitting all direction 360-degree and we
placed our detector at the right angle
or you can place at any other angle as
long as not daily capturing the incident
lab in the first part of this experiment
we are asked to set an arbitrary
excitation wavelength you want to
measure the emission spectrum of Queenan
we can make a more informed choice of
this arbitrary excitation wavelength by
looking at the uv-vis absorption
spectrum of Queenie so you can look at
the absorption maximum and choose that
as I citation wavelength for these
arbitrary values so let's say we found a
wavelength to be at par 350 nanometer so
we can actually use these as our
arbitrary excitation wavelength so we
will use this arbitrary wave length to
exit our sample and the typical emission
spectrum of Queenie will look something
like this we have the y-axis as
fluorescence intensity and then on the
x-axis we have the wavelength this
particular wavelength here is not the
excitation of line is the emission
wavelength that we measure so let's say
we set it to scan from 300 nanometer to
section o meter so this is pure Vida
emission wavelength for cleaning sample
so it may look something like this so
for example let's say we find out this
peak is about 450 nanometer this will be
the emission thing for creaminess which
correspond to this particular energy gap
here for the first sense emission okay
so in summary the purpose of running an
emission spectrum is to find the
emission peak for the first compound
that you interested in by setting an
arbitrary excitation wavelength to exile
sample so internet for mental design
when we are measuring the emission
spectrum of Queenan
we get to set the arbitrary excitation
wavelength so in other word this is
actually fixed we get to set this
okay and then in this case the emission
wavelength is the variable because we
scan from 300 meter to 600 nanometer
okay so after figuring out the emission
thing of cleaning from the emission
spectrum next we're gonna find the
excitation wavelength that give us the
highest emission intensity for this
particular emission peak here and this
is the purpose of running an excitation
spectrum so internal instrumental setup
you will be the same as the emission
spectrum because we are using the same
process machine so we have a sample in a
quad cell and then we have the
excitation source and then we have the
detector and the right angle to the
excitation source so what's the
different between an emission spectrum
and excitation spectrum since the
purpose of running an excitation
spectrum is to find out the excitation
wavelength they give us the highest
emission intensity for the emission
thing that we found furiously so this
one we set the detector to only detect
the wavelength the emission peak which
is 450 nanometer this is the information
that we obtain from the emission
spectrum and then for the excitation
wavelength we use a range of excitation
lengths to try to figure out which one
will give us a highest emission
intensity so that's why we will set the
excitation wavelength from Masari 250
nanometer to 600 nanometer so this will
be a range of excitation wavelength that
we're gonna use so I used these
excitation lengths to xio sample and
then you have emission in 360 degree so
it's just like the one that we see in
previously in the emission spectrum but
we set the detectors in a way that you
only detect the wavelength and this
particular emission thing that we are
interested in okay so in terms of the
excitation spectrum is a chase way
similar to the emission spectrum so it's
like same same but different because for
this particular intensity
the first intensity well there we have
for the y-axis we actually looking at
the first intensity of this 450
nanometer okay so you can see there's a
difference between the emission spectrum
in the excitation spectrum for the
emission spectrum right this emission
intensity correspond to all these
different ways like that we are looking
at okay so these are the put the
emission wavelength for this particular
wavelength this and intensity that
correspond to this particular wave
length however what the excitation
spectrum this intensity here is only
correspond to the emission peak that we
obtain from there so in this case I only
correspond to the 115 nanometer okay how
about the x-axis then so for the
excesses of the excitation spectrum you
will be the wavelength but in this case
it's not the emission wavelength but
it's the wavelength they were used for
excitation so this is one of the key
difference between excitation spectrum
and emission spectrum this will blend
here the y axis here is the excitation
wavelength that we try from 250 to 600
nanometer okay so you may obtain a
spectrum like this if you have to pick
something at this okay so based on this
particular excitation spectrum we can
see that this particular wavelength
actually give us the highest emission
intensity for the emission thing at 450
right this will give the highest
intensity so in other words when we
choose the excitation wavelength that
we're gonna use for subsequent
investigation we're gonna choose this
excitation wavelength they give us the
highest emission intensity at this
particular image and pick we obtained
from the emission spectrum so in summary
in terms of the experimental parameter
there's a key difference between
emission spectrum and excitation
spectrum in the emission spectrum the
excitation wavelength is fixed this is
one of the arbitrary values that we
choose at the beginning of the
experiment
and we are trying to find the emission
peak by measuring the emission of the
sample from 300 to 600 nanometer but for
the case of excitation spectrum the one
that we fix is actually the emission so
we fixed the emission at 450 nanometer
in this case because this is the
emission peak that we obtained from the
emission spectrum and then we scan
across from 250 to say Hara nanometer
try to find a suitable excitation
wavelength they give us the highest
emission intensity for this particular
emission peak here okay so hopefully
after watching this video you have a
better idea of the key difference
between the emission spectrum and the
excitation spectrum and have a better
appreciation of the experimental design
behind this person and firmly hope you
have enjoyed this video and see you in
the lab soon bye

[Music]

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emission spectrum::noun | Spocien Dictionary

emission spectrum

noun

/ɪ'mɪʃən_'spɛktrəm/

spectrum of electromagnetic radiation emitted by a self-luminous source

Type	Words
Type of	spectrum

Examples of emission spectrum

emission spectrum

Top right is VLA spectrum showing radio emission from Carbon Monoxide molecules.

From the sciencedaily.com

Their PL emission spectrum overlaps with spectrally broad leaky modes of the PhC.

From the nature.com

This is the first time a near-infrared emission spectrum has been obtained for an exoplanet.

From the sciencedaily.com

A material's blackbody spectrum is a spontaneous emission spectrum determined by its temperature.

From the en.wikipedia.org

A second, related, puzzle was the emission spectrum of atoms.

From the en.wikipedia.org

Hydrogen emission spectrum lines in the visible range.

From the en.wikipedia.org

The upper inset shows the persistent luminescence emission spectrum recorded at 1 h after the stoppage of the irradiation.

From the nature.com

The usual metals are sodium and mercury owing to their visible spectrum emission.

From the en.wikipedia.org

An example is the emission spectrum of nebulae.

From the en.wikipedia.org

How to pronounce emission spectrum in English?

emission spectrum::noun | Spocien Dictionary

abandonment

Related words

Examples of emission spectrum

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