Little Dog

LCMO data (x = 0.16-0.22)

Data points for LCMO (x = 0.16 - 0.22)

16%	18%	20%	22%
3	3	3	3
20	20	20	20
40	40	40	40
60	60	60	60
80	70	70	80
100	100	100	100
120	120	120	105
135	135	135	120
140	140	140	135
150	150	150	140
155	155	155	150
160	160	160	155
170	170	170	160
175	175	180	170
180	180	185	175
185	185	190	180
195	190	195	185
200	195	200	190
210	200	210	195
220	210	225	195
250	225	250	200
260	250	270	210
270	270	275	220
300	275	308	250
308	308	320	260
340	320	348	270
348	348	398	300
398	398	448	303
448	448	498	345
498	498	555	376
555	555		406
			435
			465
			495
			524
			555

Preliminary results by ananlyzing LCMO (16%-22%)

This is the Sigma^2 vs T for different samples with doping level x = 16%,18%,20%,22%.

A sharp increase in Sigma^2 (Sigma is the width of the Mn-O pair distribution function "PDF")near Tc.

The magnitude of the step decreases rapidly with decreasing x.

The value of Sigma^2 at low T is close to the value for zero-point motion for x = 22%, but increases substantially for lower x, which indicates that in the magnetized state there is either a large Jahn-Teller distortions or a static distortion which remains at low T.

The end compound LaMnO3 has a large J-T distortion, so we think it's caused by J-T distortion.














Also the magnetization at low T is small for lower x, indicating that not all of the sample is ferromagnetic, regions of antiferromagnetism may remain.

Mn-O standard for LCMO low doping samples and LSCO

I tried to use FEFF to calculate the Mn-O function from Norby's LaMnO3 and Poe*'s CaMnO3, and combine them with x = 0.2 to make a new standard, but failed. The XI and NX for them are different, so the computer can't just add them together. Tried with FEFF8.20 and FEFF6.

Then I tried to make the similar standard for Co-O, failed at the same problem.

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